Man-Made Structures to Recognize

1.See a House

A house is a free-standing building made to shelter one household, and you know one on sight by its human scale and the kit of parts: walls of brick, timber, or stucco rising one or two stories to a pitched or gabled roof, punctuated by windows, a front door, and usually a chimney, set on its own plot with a yard or garden rather than stacked into a tower. The world's most celebrated single house is Frank Lloyd Wright's Fallingwater in Pennsylvania (1937), whose cantilevered concrete terraces float straight over a waterfall.

2.See a Fence

A fence is a freestanding barrier that encloses or divides land, built from a line of upright posts linked by horizontal rails, pickets, wire, or panels — lighter and more open than a solid wall, and recognizable by its repeating vertical members and the boundary it traces along a yard, field, or road. The most iconic example is the white picket fence, the pointed-top wooden style fronting cottages and homes across New Zealand, the United States, and beyond.

3.See a Shed

A shed is a small, single-storey roofed outbuilding used for storage, tools, or a workshop — you'll know one by its compact boxy footprint, a single pitched (gable, gambrel, or lean-to) roof, one human-sized door (often a wide pair), and timber, cedar-shingle, or corrugated-metal walls, usually tucked at the edge of a garden, allotment, or yard rather than attached to a house. A famous real example is the humble backyard shed in Hobart, Tasmania where Australia's Men's Shed community movement took root, now echoed in thousands of communal "Men's Sheds" worldwide.

4.See a Garage

A garage is a walled, roofed structure built to shelter one or more motor vehicles — spot one by its wide vehicle-sized door (a roll-up panel door or hinged swing doors) set into a low single-story box with a gable or flat roof, often standing detached from a house or built into its side, with a paved apron or driveway running up to the opening. The world's most famous example is the HP Garage at 367 Addison Avenue in Palo Alto, California — a humble redwood one-car garage where Bill Hewlett and David Packard founded Hewlett-Packard in 1939, now a California Historical Landmark dubbed the "Birthplace of Silicon Valley."

5.See a Barn

A barn is a large farm outbuilding for sheltering livestock, storing hay, grain, and equipment — recognizable by its tall boxy timber or steel frame, broad gabled or distinctive double-pitched "gambrel" roof, big sliding or hinged doors wide enough for a wagon or tractor, and an upper hayloft door, all set in open farmland and very often painted barn-red with white trim (sometimes paired with a tall cylindrical silo). One famous real example is the Starke Round Barn in Red Cloud, Nebraska, the largest freestanding round barn in the United States.

6.See a Church

A church is a building for Christian worship, and you can spot one by its upward-reaching silhouette: a tall steeple, spire, bell tower, or dome crowning the roof, often paired with a cross, a large rose or arched window, and a prominent front entrance, set apart from ordinary buildings on a town square or hilltop. Notre-Dame de Paris is the textbook example, with its twin western towers, soaring spire, flying buttresses, and great circular rose window.

7.See a School

A school is a building purpose-built for teaching the young, recognizable by its repeating grid of large, evenly spaced windows (to flood many classrooms with daylight), a wide central entrance often flanked by symmetrical wings, and a hall, bell tower, or cupola crowning the roof; you'll spot one by its institutional scale set back behind a flag-poled yard or playground, frequently in brick or stone with a carved name and date over the door. A famous example is Eton College in Windsor, England (founded 1440), whose brick Tudor courtyards and twin-turreted Lupton's Tower are among the most recognizable school buildings in the world.

8.See an Apartment Building

A multi-story residential building divided into many self-contained dwelling units (apartments/flats), the everyday home for a huge share of the world's city-dwellers. You know one on sight by its tall, boxy mass and the grid of repeating, near-identical windows and stacked balconies marching across the facade — the visual signature of many separate homes stacked under one roof — usually with a single shared street entrance, mailboxes or buzzer panel, and interior stairs or an elevator. They range from ornate stone landmarks like New York's The Dakota (1884) overlooking Central Park, to vast social-housing blocks like Vienna's kilometre-long Karl-Marx-Hof, to glassy modern high-rise towers; the constant tell is that one building holds many front doors.

9.See an Office Building

An office building is a structure built to house desk-based work — recognizable by its stack of identical floors of windows wrapped in a repeating grid (a curtain wall of glass and metal, or punched windows in stone or concrete), a lobby at street level, and a setting in a downtown core or a landscaped suburban office park rather than alongside homes; the giveaway is the relentless modular regularity, often topped by a company name or logo. A famous example is the bronze-and-glass Seagram Building (1958) on Park Avenue in New York, Mies van der Rohe's set-back tower with its open plaza that became the template for the modern corporate skyscraper.

10.See a Warehouse

A warehouse is a large utilitarian building for storing goods in bulk — spot one by its long, low, boxy silhouette with broad blank walls (corrugated metal or tilt-up concrete), a flat or shallow-gabled roof, few windows, and a row of truck-height loading-dock doors along one side, usually set in an industrial park beside wide vehicle aprons. A famous example is Amazon's vast fulfillment centers, like the one at Warrington in the UK.

11.See a Bridge

A bridge is a structure built to carry a path, road, or railway across an obstacle like a river, valley, or another road. You can spot one by its raised deck — a level span lifted clear of the gap below — held up by some visible support system: tall towers strung with sweeping cables (suspension), a bowed arch beneath or above the roadway (arch), or simple piers marching across the water. A world-famous example is San Francisco's Golden Gate Bridge, whose orange-red towers and draped main cables make it instantly recognizable.

12.See a Gas Station

A roadside facility that sells motor fuel, identifiable on sight by its flat, wide canopy raised on slender columns to shelter a row of fuel pumps (each a waist-high cabinet with a hose and nozzle), a brightly branded pole sign, and a small kiosk or convenience shop set on an open paved forecourt beside the road. A famous example is the Art Deco Tower Station and U-Drop Inn (1936) in Shamrock, Texas, whose tulip-crowned Conoco tower is one of Route 66's most photographed landmarks.

13.See a Water Tower

A water tower stores water high enough for gravity to help maintain pressure and meet changing demand. Common forms include a rounded or cylindrical tank on a single column, a tank carried by an open steel frame, and an enclosed standpipe tower. The 1869 Chicago Water Tower is a famous historic variation: its Gothic Revival masonry shell originally housed a 138-foot standpipe rather than the bulbous elevated tank suggested by the familiar ‘tank on a stalk’ silhouette.

14.See a Hotel

A hotel is a building that lodges paying overnight guests, recognizable by its repeating grid of identical guest-room windows (often with small balconies) stacked across many floors, a prominent ground-floor entrance with a covered porte-cochere or portico where guests arrive, and usually the hotel's name spelled out in signage on the facade or roofline; grander examples crown the structure with turrets, mansard roofs, or rooftop terraces. A famous real example is Singapore's Raffles Hotel, the gleaming white colonial-style landmark with arched verandahs that gave its name to the Singapore Sling cocktail.

15.See a Hospital

A hospital is a building dedicated to medical care, recognizable by its large multi-storey or multi-wing institutional bulk, ranked rows of identical windows along long ward blocks, prominent main entrances marked with red-cross or "Emergency"/"A&E" signage and a covered ambulance bay, and—on landmark older ones—a central domed or columned administration block; a famous example is the 1889 red-brick, dome-crowned Billings Administration Building of The Johns Hopkins Hospital in Baltimore.

16.See a Factory

A factory is a large building or complex where goods are manufactured, identifiable by its utilitarian bulk: long multi-storey blocks or wide single-storey sheds of brick, concrete, or steel-and-glass, punctuated by tall chimneys (or rooftop vents), rows of identical windows, loading bays, and often a sawtooth roofline, usually set in an industrial zone beside rail lines, a canal, or a road for moving raw materials in and finished goods out. A famous example is Fiat's Lingotto in Turin, Italy — a 1923 reinforced-concrete car plant so vast it had a banked test track on its roof.

17.See a Shopping Mall

A shopping mall is a large enclosed retail complex housing many separate stores along interior pedestrian walkways. You recognize one by its long, climate-controlled concourses lined with shopfronts stacked over two or more galleried levels, the central skylit atrium with escalators and a food court, and the surrounding sea of parking — as at the Mall of America in Bloomington, Minnesota, or the grand 19th-century glass-vaulted arcade of Milan's Galleria Vittorio Emanuele II.

18.See a Parking Garage

A parking garage (multi-storey car park) is a building made for stacking cars on several levels, and you spot one by its giveaway silhouette: a blocky structure of repeating open-sided concrete or precast decks, with low gaps between floors where you can glimpse parked cars and the sloping internal ramps that thread between levels, often topped or flanked by a stair-and-elevator tower and a big "P" sign at the entrance. A celebrated real example is 1111 Lincoln Road in Miami Beach, the Herzog and de Meuron garage whose dramatic angled columns and open lit decks turned a humble car park into an architectural landmark.

19.See a Silo

A silo is a tall, sealed storage tower for bulk grain or fermented silage — you'll know one by its smooth cylindrical drum (often a cluster of them in a row), a domed or conical cap, and its lonely setting beside a barn or rail line on farmland; concrete-stave, steel, and the unmistakable cobalt-blue Harvestore models are the classic forms, with the vast prairie grain-elevator batteries of the North American Great Plains being the most famous examples.

20.See a Greenhouse

A greenhouse (glasshouse) is a building with translucent walls and roof — glass or rigid/film plastic panels held in a slender metal or wooden frame — that traps sunlight to grow plants in a warmed, sheltered interior; you know one on sight by its near-fully-glazed envelope (often a peaked or arched roof), visible structural ribs, roof vents, and a setting full of greenery, from a backyard plot to a botanical garden. The grandest example is the Palm House at London's Kew Gardens (1844–48), a soaring whale-ribbed dome of curved glass and wrought iron that is the world's most important surviving Victorian glasshouse.

21.See a Gazebo

A gazebo is a freestanding garden pavilion you spot by its open, wall-less sides and solid roof perched on slender posts above a small raised platform — almost always built on a round, hexagonal, or octagonal footprint so it looks the same from every angle, frequently crowned with a little cupola or weathervane and ringed by railings or built-in benches. Salzburg's Hellbrunn Palace gardens hold perhaps the most famous one of all: the white glass-paned pavilion from The Sound of Music, where "Sixteen Going on Seventeen" was filmed.

22.See a Clock Tower

A clock tower is a freestanding or building-topping tower built specifically to carry one or more large public clock faces high enough to be read across a town. You can spot one by the giant illuminated dial (or several, one per side) set near the top of a tall, narrow masonry shaft, usually crowned by a belfry, a pyramidal roof or spire, and often a bell that chimes the hours — most famous of all is London's Elizabeth Tower, the Big Ben tower at the Palace of Westminster.

23.See a Lighthouse

A lighthouse is a tall, tapering tower built on a coast, headland, or rocky islet to warn and guide ships, crowned by a glass-walled lantern room (often ringed by a black railed gallery) that houses the light; many wear bold paint patterns called daymarks — spiral stripes, horizontal bands, or a solid white shaft — so they're recognizable by day as well as by their flashing beam at night, and they usually stand beside a keeper's house in an exposed seaside setting. The classic tell is that slender stone-or-brick cone topped by the dark lantern cap, like North Carolina's Cape Hatteras Lighthouse with its unmistakable black-and-white candy-stripe spiral.

24.See a Tunnel

A tunnel is an underground or underwater passage bored through rock, earth, or beneath water to carry a road, railway, or canal. You know one by its mouth: a portal — an arched or rectangular opening framed by a reinforced concrete or cut-stone facade — set into a hillside, mountain flank, or riverbank, opening onto a long, enclosed bore lined with concrete or masonry and strung with continuous overhead lighting that recedes to a distant point of daylight. The Channel Tunnel, running 50 km beneath the seabed between England and France, is among the most famous in the world.

25.See a Stadium

A stadium is a large open-air venue built for sports and spectacle, recognizable by its oval or bowl shape: tiers of seating that rake steeply upward in a continuous ring around a central pitch or track, often crowned by a cantilevered roof, floodlight pylons, or a signature arch. Materials run from poured concrete and steel to translucent membrane facades that glow when lit. A famous example is Rio de Janeiro's Maracanã, whose vast open oval hosted two World Cup finals.

26.See a Dam

A dam is a barrier built across a river or valley to hold back water, recognizable as a tall, broad wall spanning between two valley or canyon walls with a reservoir pooled on the upstream side and often a much lower river or churning spillway discharge below. The tell-tale signs: a thick concrete or earthen face that is either gently curved upstream (an arch dam, like Glen Canyon) or a massive straight wedge (a gravity dam), usually topped by a road or walkway along its crest, with intake towers, gated spillways, or a powerhouse at its base. The most famous example is the Hoover Dam on the Colorado River between Nevada and Arizona, whose graceful curved Art Deco wall and twin intake towers rising from Lake Mead are instantly recognizable.

27.See a Skyscraper

A skyscraper is a very tall, continuously habitable high-rise building — typically 40+ stories — held up by a steel or reinforced-concrete frame rather than its outer walls, which is what lets it climb so high. You can spot one by its sheer slenderness and height relative to everything around it, its repetitive grid of identical floors stacked into a curtain wall of glass and metal, and a tapering or stepped-back crown (often an antenna or spire) at the top; they cluster in the downtown cores of major cities. The Empire State Building in New York, with its setback Art Deco massing and needle-like spire, is the archetypal example.

28.See a Windmill

A windmill is a tall tower-mill that converts wind into rotary power, recognizable on sight by its four (sometimes more) long lattice-and-canvas sails radiating from a hub near the top, set on a tapering brick, stone, or thatched-and-timber tower that often sits beside water or atop open farmland. The most famous gathering is the row of nineteen 18th-century mills at Kinderdijk in the Netherlands, a UNESCO World Heritage site whose silhouettes reflected in the polder canals are the classic image of the form.

29.See a Wind Turbine

A wind turbine is a tall, slender tower (typically white or pale grey, 80-150 m) topped by a box-shaped nacelle and a single three-bladed propeller-like rotor that swivels to face the wind — the unmistakable tell is that lone trio of long, tapering blades turning slowly against open sky, set where the wind is steady: ridgelines, plains, or planted in rows out at sea on yellow foundations. A famous real example is the Barrow and Thornton Bank offshore wind farms in the North and Irish Seas, whose turbines march in misty ranks across the water.

30.See a Castle

A castle is a fortified residence built for defense, the signature monument of medieval Europe and the most instantly recognizable "fairy-tale" structure in the world — worth knowing on sight.

31.See a Pier

A pier is a long, narrow platform raised on rows of slender pillars (piles) that marches straight out from the shoreline over the water, so you spot one by its open lattice of legs standing in the sea and a flat deck running well past the breakers — pleasure piers add the tell-tale crown of a pavilion, arcade, or fairground rides (a Ferris wheel or roller coaster) perched at the far end. England's Brighton Palace Pier (opened 1899) is the classic example, its cast-iron legs and domed amusement halls glowing out over the Channel.

32.See a Hangar

A hangar is the big enclosed shed where aircraft are sheltered, parked, and repaired — and you know one on sight by its enormous single doorway: a span far wider than any normal building, sealed by huge sliding or folding doors (or a curved roll-up) that swallow a whole plane, set under a low arched or gently pitched roof with no interior columns to block the wing-span. Britain's Delta Jets hangar at Kemble Airport is a textbook example, its green arched shed yawning open to roll a Hawker Hunter jet straight onto the apron.

33.See a Grain Elevator

A grain elevator is a tall tower-and-bin facility that lifts harvested grain by a vertical conveyor (the "leg") and stores it in stacked vertical chambers — the workhorse landmark of farm country and port terminals. Spot one by its silhouette: a cluster of tall, slender vertical cells (slatted-wood cribbed boxes on older prairie elevators, smooth concrete or corrugated-steel cylinders on newer ones) topped by a taller boxy "headhouse" or cupola that caps the lifting machinery, almost always standing right beside a railway siding or a waterfront so grain can be loaded out — older ones often carry the grain company's name painted huge down the side. A famous example is the Inglis Grain Elevators National Historic Site in Manitoba, Canada, the last complete vintage row of standard-plan wooden prairie elevators still standing.

34.See a Bell Tower

A bell tower is a tall, slender structure built to house bells and ring them out over a town — recognizable as a freestanding (or church-attached) vertical shaft, usually square or round, that's much taller than it is wide, with an open belfry near the top showing arched louvered openings where the bells hang, often capped by a spire, pyramid, or dome. Its tell-tale signs are those open bell-chamber arches high up, the masonry or brick shaft, and a placement beside a church, cathedral, or town square; the world's most famous example is the Leaning Tower of Pisa, the tilting white-marble campanile of Pisa Cathedral in Italy.

35.See a Cooling Tower

A cooling tower is a tall industrial structure that sheds waste heat from a power plant or factory by evaporating water, and you can spot one by its unmistakable silhouette: a hollow concrete shell pinched into an hourglass curve (a hyperboloid), flaring wide at the base, narrowing at the waist, and opening again at the rim — often crowned by a lazy plume of white steam. The eight gracefully curved giants at England's now-demolished Didcot Power Station were a landmark for miles, and the same shape rings nuclear and coal stations the world over.

36.See a Mosque

A mosque is a Muslim place of worship, and you can usually spot one by its silhouette: a large central prayer hall often crowned by one or more rounded domes, flanked by one or more tall, slender towers called minarets (from which the call to prayer is traditionally given), with arched arcades, and—wherever you stand inside—a wall niche (mihrab) angled toward Mecca; styles range from the marble-and-tile, multi-domed Ottoman form to the famous mud-brick, palm-beam-studded Great Mosque of Djenné in Mali. A textbook example is Istanbul's Sultan Ahmed Mosque, the "Blue Mosque," whose cascade of domes and half-domes ringed by six pencil-thin minarets is one of the most recognizable skylines in the Islamic world.

37.See a Cathedral

A cathedral is the principal church of a diocese — the one that houses a bishop's throne (the cathedra) — and on sight it reads as a soaring stone church laid out as a Latin cross, with a tall nave flanked by lower aisles, a crossing transept, and a great west front of carved portals, statue galleries, and a circular rose window crowned by towers or spires; the celebrated twin-spired Gothic giant of Cologne Cathedral in Germany is a textbook example.

38.See a Hindu Temple

A Hindu temple is a place of worship built to house a deity in its small, dark inner sanctum (the garbhagriha) — and you can spot one by the tower that rises directly over that sanctum. In the north (Nagara style) it's a tall, gently curved beehive-shaped spire called a shikhara, often clustered with smaller echoing peaks like a stone mountain range; in the south (Dravidian style) it's a stepped pyramidal tower (vimana), and the temple's outer gateways become soaring gopurams encrusted top to bottom with brightly painted gods, demons, and animals. Look for richly carved stone walls, a kalasha finial crowning the peak, and a compound built around that sanctum-and-tower core; the colossal granite vimana of the 11th-century Brihadeeswarar Temple in Thanjavur, India, is one of the most famous examples in the world.

39.See a Synagogue

A synagogue is a Jewish house of worship and communal gathering, recognizable by a prominent facade often crowned with a Star of David and built around an interior Torah ark (the cabinet, set on a raised platform behind ornate doors, that holds the Torah scrolls) facing toward Jerusalem. Many landmark synagogues wear the Moorish Revival look that swept the 1800s — striped or polychrome stonework, horseshoe and pointed arches, twin towers topped with onion or bulbous domes, and a large circular rose window over the entrance — as seen in Budapest's Dohány Street Synagogue, Europe's largest, whose twin gilded onion-domed towers are an unmistakable landmark.

40.See a Pagoda

A pagoda is a tiered tower from Buddhist (and sometimes Taoist or Hindu) tradition across East and South Asia, built as a temple shrine or reliquary. You recognize one by its stack of receding storeys, almost always an odd number from three to thirteen, each ringed by its own wide upward-curving eave, with the whole tapering tower crowned by a slender vertical finial or spire; early ones are red-lacquered or bare wood and later ones brick or stone, and you will nearly always find it standing in a temple precinct. The fire-engine-red five-eaved pagoda beside Senso-ji temple in Tokyo's Asakusa is a textbook example, while Japan's Horyu-ji holds the oldest one of all, a 7th-century wooden tower among the oldest surviving wooden buildings on Earth.

41.See a Palace

A palace is a grand residence built for a monarch, head of state, or high nobility — you can spot one by its monumental scale and symmetrical wings spreading out from a central block, a long ceremonial façade lined with rows of tall windows, ornamental stonework, and a setting that announces status: a forecourt, formal gardens, or a commanding hilltop. London's Buckingham Palace, with its broad neoclassical front facing a gated forecourt and the Victoria Memorial, is the textbook example.

42.See a Fortress

A fortress is a large fortified military stronghold built to withstand siege — look for thick, high defensive walls (often with battlements, towers, or angular star-shaped bastions jutting outward), a commanding position on a hilltop, rocky plateau, or island, and stout stone or earthwork construction enclosing inner buildings. A famous example is Hohensalzburg Fortress, the vast white medieval stronghold crowning the hill above Salzburg, Austria.

43.See a City Wall

A city wall is a continuous defensive barrier of stone or brick raised around a town to protect it, and you can spot one by its tell-tale parts: a tall curtain wall topped with toothed merlon battlements, regularly spaced projecting towers (often round bastions or square gate-towers), and fortified gateways piercing the ring — typically wrapping a dense old town and following the lay of the land. The walls of Ávila in Spain are a textbook example: nearly two and a half kilometres of honey-colored granite studded with 88 semicircular towers, among the best-preserved medieval circuits in the world.

44.See a Breakwater

A breakwater is a man-made barrier built out into open water to absorb the force of waves and create calm, sheltered water behind it for a harbour, marina, or shoreline. You can recognize one by its long, low, linear or curving wall running parallel to or out from the coast — often a "rubble-mound" pile of boulders or interlocking concrete armour units (the four-legged tetrapods being unmistakable), sometimes a sheer concrete or masonry wall, frequently capped at its seaward tip with a small lighthouse or beacon and standing slightly detached from the land it protects. A famous example is the Plymouth Breakwater in Devon, England — a 1,560-metre stone barrier laid across Plymouth Sound in the 1810s, with a granite lighthouse on its western end.

45.See a Canal Lock

A canal lock is a water elevator: a stone or concrete chamber sealed at each end by a pair of tall wooden or steel "miter" gates that meet in a shallow V pointing upstream, each swung by a long horizontal balance beam you can spot from the towpath — flood or drain the chamber and a boat rises or falls to the next water level, with flights of them famously climbing a hillside like a watery staircase at Caen Hill on England's Kennet and Avon Canal.

46.See a Railway Terminal

A railway terminal (or terminus) is a grand passenger station built where the tracks end rather than pass through, so you spot one by its monumental "head house" entrance facing the city — a wide ornate facade with a clock and a row of tall arched windows or a colonnade — opening onto a soaring main concourse and a fan of platforms tucked under a vast iron-and-glass arched "train shed" roof. A famous example is New York City's Grand Central Terminal, its Beaux-Arts limestone front crowned by the Glory of Commerce sculpture group and its celestial-ceilinged Main Concourse instantly recognizable worldwide.

47.See an Airport Terminal

An airport terminal is the passenger building where travelers check in, pass through security, and board aircraft — recognizable by its long, low, glass-walled facade fronted by curving access roads and drop-off lanes, a vast column-free departure hall under a sweeping roof (often a lattice, vault, or shell held up by branching "tree" columns), rows of check-in desks, flight-information boards, and jet bridges reaching out to planes on the apron behind it. A famous example is Eero Saarinen's swooping, bird-winged TWA Flight Center at New York's JFK Airport (1962), one of the most beloved terminals ever built.

48.See a Bunker

A bunker is a hardened defensive shelter built to shield people, weapons, or supplies from blasts and gunfire — recognizable by its squat, monolithic mass of thick reinforced concrete, often half-buried in an earth berm or hillside, with a flat or rounded weatherworn roof and narrow horizontal slits (embrasures or gun ports) instead of windows; a famous example is the Longues-sur-Mer battery in Normandy, France, whose casemates still hold their original Atlantic Wall guns peering out toward the sea.

49.See an Aqueduct

An aqueduct is a bridge-like channel built to carry flowing water across a valley or low ground, recognizable by its long run of tall arches — often stacked in two or three tiers — striding at a near-level height so the water keeps gently descending. Unlike a viaduct (which carries a road or railway), an aqueduct's deck hides a water channel. The Pont du Gard in southern France and the Aqueduct of Segovia in Spain are the most famous Roman survivors.

50.See a Viaduct

A viaduct is a long bridge that carries a railway or road on a continuous run of repeated equal spans high above the ground — recognize one by its march of identical arches or slender piers stepping across a wide valley or low-lying land (rather than a single span over a river), most often in stone, brick, or concrete, with the deck held at a near-constant height the whole way across. The Glenfinnan Viaduct in the Scottish Highlands, with its sweeping curve of 21 concrete arches, is a famous example (and a star of the Harry Potter films).

51.See a Solar Farm

A solar farm (photovoltaic power station) is a utility-scale field of dark, rectangular solar panels mounted in long, evenly spaced parallel rows on low metal racks, tilted to face the sun and often blanketing flat, open land in a deep blue-black grid that reads as glassy and uniform from a distance. Tell-tale signs are the repeating angled rows with bare access lanes between them, scattered low inverter and transformer boxes, and a perimeter fence around an otherwise empty plain. A famous example is the Topaz Solar Farm on California's Carrizo Plain, one of the world's largest, with around nine million panels spread across roughly 9.5 square miles.

52.See an Obelisk

A tall, slender four-sided stone pillar that tapers as it rises and is capped by a small pyramid-shaped point (the pyramidion) — usually a single monolith of granite, often carved with hieroglyphs or inscriptions and set on a low plinth in the center of a plaza; the most famous is the 555-foot Washington Monument on the National Mall, while ancient Egyptian originals like the Luxor Obelisk in Paris's Place de la Concorde show the gleaming gilded tip and carved shaft of the true form.

53.See a Minaret

A minaret is the tall, slender tower attached to a mosque, from which the call to prayer is traditionally given; spot one by the narrow vertical shaft (square, cylindrical, or octagonal) topped with one or more railed balconies and capped by a small dome, conical cap, or metal finial, almost always standing beside a domed prayer hall. Famous examples range from the slender, balconied "pencil" minarets of Istanbul's Blue Mosque to the unmistakable helical ramp of the Malwiya at Samarra in Iraq.

54.See a Market Hall

A market hall is a permanent, roofed building housing rows of vendor stalls — recognizable by its long single-volume interior under an open iron, timber, or steel-truss roof (often with a glazed clerestory or skylights for daylight), slender cast-iron columns, and big arched or glazed entrances, usually set right on a town square or main street. The 19th-century iron-and-glass type is the classic tell; Madrid's Mercado de San Miguel — a glass-walled cast-iron pavilion of 1916 — is one of the most famous surviving examples.

55.See a Public Bath

A public bath is a communal bathing facility where people wash and soak together, recognizable by its large shared water basins set into tiled or stone floors, rows of low washing stations along the walls, and often grand symmetrical architecture or a distinctive chimney for heating water; spot one by the open pool surrounded by columns, statues, or a painted mural (a Mount Fuji scene is the giveaway in a Japanese sento). The Roman Baths in Bath, England, are the world's most famous example, with their hot-spring-fed turquoise Great Bath ringed by Victorian terraces and columns.

56.See a Capitol or Parliament

A capitol or parliament is the seat of a nation's or state's legislature — the grand, monumental building where elected lawmakers meet, and almost always the single most ceremonial structure in a capital city. You can spot one by its civic-temple grandeur: a long symmetrical facade with a tall central element you can't miss, usually either a great dome rising over a central rotunda (the neoclassical "capitol" look, with columned porticoes and pale stone) or a soaring clock or flag tower amid pinnacled Gothic Revival stonework; it typically sits on a commanding site — a hilltop, a broad plaza, or a riverbank — set apart from ordinary commerce. The United States Capitol in Washington, D.C., with its white cast-iron dome and twin chamber wings, is the textbook example; Britain's Palace of Westminster (the Houses of Parliament), with its Gothic towers and the Elizabeth Tower clock beside the Thames, is its equally famous counterpart.

57.See an Opera House

A purpose-built theatre for opera and ballet, an opera house is recognizable as a large, grand performance hall with a deep stage tower (fly tower) rising behind a public facade; classic ones wear ornate stone fronts with columned loggias, arched entries, balustrades, gilded statuary and a copper-domed or pedimented roof, set on a prominent civic square, while modern ones can take sculptural shapes like Sydney's white sail-shell vaults. The Sydney Opera House on its harbour and the lavish Palais Garnier in Paris are the two most famous examples.

58.See an Observatory

An observatory is a building made to house a telescope for studying the night sky, and you can spot one by its signature rotating dome — a smooth hemispherical cap, often white or metallic, with a tall vertical slit (the shutter) that opens to aim the telescope at a slice of sky. They usually crown a hilltop or mountain summit for dark, steady air, sometimes with several domes clustered on one ridge; the Griffith Observatory in Los Angeles, with its Art Deco facade and trio of copper domes, is one of the most recognizable in the world.

59.See an Amphitheater

A freestanding amphitheater is unmistakable: a fully enclosed oval (not a half-circle like a Greek theater) of stone seating tiers ringing a central performance floor — the "arena" — with the exterior wrapped in stacked rows of repeating arches. Spotting that ellipse of round-arched arcades, often weathered honey-colored stone, marks one on sight; the Colosseum in Rome is the definitive example, with the arenas at Pula (Croatia), El Jem (Tunisia), and Nîmes (France) showing the same form remarkably intact.

60.See an Abbey

An abbey is a monastery (or former one) built around a great church for a community of monks or nuns, recognizable by a tall cruciform church with a long nave and a central or twin-towered facade, flanked by a square cloister courtyard ringed with covered walkways and ranges of monastic buildings (chapter house, refectory, dormitory) — often seen today as roofless stone ruins in the countryside. A famous example is Westminster Abbey in London; Mont Saint-Michel rises as a fortified abbey on a tidal island in Normandy.

61.See a Torii Gate

A torii is the gateway that marks the entrance to a Japanese Shinto shrine — the threshold between the everyday world and sacred ground. You'll know one by its simple, unmistakable silhouette: two upright posts crowned by two horizontal beams, the top one (the kasagi lintel) often sweeping upward at the ends like wings, with a second straight beam (the nuki) tied just below it. Most famous is the great vermilion "floating" torii of Itsukushima Shrine near Hiroshima, which appears to rise straight out of the sea at high tide — though they range from bright red-orange painted wood to bare cypress, weathered stone, and even bronze, and can stand alone or repeat by the hundreds into a tunnel, as in Kyoto's Fushimi Inari senbon-torii.

62.See a Stupa

A stupa is a Buddhist monument built to enshrine relics — recognizable as a solid, windowless dome (hemispherical, bell-, or mound-shaped) raised on a circular or square base, crowned by a square railing-box (harmika) and a tapering spire of stacked discs or rings, often whitewashed, gilded, or bare stone and ringed by a railing or prayer flags; you cannot go inside one. The most famous example is the Great Stupa at Sanchi, India (3rd century BCE), the classic bare-stone dome encircled by carved gateways.

63.See an Oil Platform

An oil (or gas) platform is a large offshore structure that drills for and pumps up petroleum from beneath the seabed — recognizable as a boxy steel topside deck bristling with cranes, flare booms, and a tall latticework drilling derrick, all hoisted high above the waves on either a forest of slender legs (fixed jackets or massive concrete columns) or buoyant pontoons tethered to the seafloor, with a helideck on top and supply boats often alongside. The most famous is Norway's Troll A in the North Sea, a Condeep concrete giant that is among the tallest structures ever moved by humankind.

64.See a Yurt

A yurt (Mongolian ger) is a portable round dwelling of the Central Asian steppe nomads — instantly recognizable by its low circular footprint, gently domed roof rising to a wooden crown-wheel (the toono/shangrak, often the only opening to the sky), walls of white or grey felt cinched by tension bands over a collapsible wooden lattice frame, and a single brightly painted wooden door, almost always standing alone on open grassland or desert. A famous real example is the cluster of felt yurts on the high meadow around Song-Köl (Son-Kul) lake in Kyrgyzstan, while the ger remains the everyday home of more than half of all Mongolians today.

65.See a Cliff Dwelling

A cliff dwelling is a multi-story stone-and-mortar village built by Ancestral Puebloan peoples directly inside a natural rock alcove or recess high on a canyon wall — you'll know one by its tiers of small, square, flat-roofed masonry rooms wedged under a sheltering overhang of sandstone or limestone, often punctuated by circular sunken chambers called kivas and tiny dark window and doorway openings, the whole settlement tucked into the cliff rather than perched on open ground. The most famous example is Cliff Palace at Mesa Verde National Park in Colorado, the largest cliff dwelling in North America with around 150 rooms and 23 kivas tucked beneath a great curving sandstone arch.

66.See a Mausoleum

A mausoleum is a free-standing, monumental building raised as a tomb to shelter the remains of one or more people above ground, rather than burying them in the earth. Recognize one by its sealed, windowless or near-windowless "house for the dead" form: a solid, symmetrical stone or marble block — often topped with a dome, obelisk, or pyramid roof, set on a raised platform with columns, an imposing doorway, and inscribed family or honorific names, usually standing alone in a cemetery, garden, or memorial plaza. The most famous example is the white marble, dome-and-minaret Taj Mahal in Agra, India, the tomb Shah Jahan built for his wife Mumtaz Mahal — and the very word "mausoleum" comes from the Mausoleum at Halicarnassus, one of the Seven Wonders of the Ancient World.

67.See a Stepwell

A stepwell is a subterranean water structure where a long flight of stairs (often a dramatic crisscross or inverted-pyramid lattice of steps lining the walls) descends many storeys down a deep masonry shaft to reach groundwater that rises and falls seasonally. Tell-tale signs on sight: an open pit set into otherwise flat ground rather than a tower; tiered stone walls of zigzagging or pyramidal steps converging toward a small pool far below; and, in the ornate ones, carved sandstone pillars, galleries, and figural panels lining the descent. India's Chand Baori at Abhaneri, Rajasthan — roughly 3,500 steps in a perfect inverted pyramid plunging 13 storeys — is the most famous example, alongside the UNESCO-listed Rani ki Vav at Patan, Gujarat.

68.See a Pyramid

A pyramid is a monumental structure whose outer surfaces slope upward from a broad polygonal base (usually square) to converge at a single point at the top — so you spot one by that unmistakable triangular silhouette from any angle. Tell-tale features: a wide flat base tapering to an apex; either smooth angled faces (like Egypt's stone tombs) or tiered "stepped" terraces with a central staircase (like Mesoamerican temple-pyramids); built of stacked stone, brick, or — in modern versions — glass and steel. The most famous example is the Great Pyramid of Giza in Egypt, the last surviving wonder of the ancient world.

69.See a Triumphal Arch

A triumphal arch is a freestanding monumental gateway built to commemorate a victory, ruler, or event — and you can spot one by its signature silhouette: a tall, rectangular masonry block pierced by either a single grand archway or a large central arch flanked by two smaller ones (a triple-bay arch), framed by engaged or detached columns, topped by a deep horizontal slab (the attic) that usually carries an inscription or relief panels, and often crowned by a bronze chariot or victory sculpture, standing alone on a plaza or astride a road rather than attached to any building. Paris's Arc de Triomphe is the world's most famous example, while Rome's triple-bay Arch of Constantine is the great surviving ancient model the form descends from.

70.See a Megalithic Stone Circle

A megalithic stone circle is a prehistoric ring of large upright stones (megaliths) set into the earth, built by Neolithic and Bronze Age communities roughly 5,000 years ago; you can spot one by the deliberate circular or oval arrangement of freestanding, weathered boulders standing alone on open moor, grassland, or hilltop, sometimes with a low surrounding bank and ditch, and occasionally capped by horizontal lintel stones. The most famous example is Stonehenge on Salisbury Plain in England, instantly recognizable by its trilithons (paired uprights bridged by a stone beam), while the British Isles hold over a thousand others such as Castlerigg, Callanish, and Avebury.

71.See a Ziggurat

A ziggurat is an ancient Mesopotamian temple-tower: a solid, terraced pyramid of receding tiers built to raise a small shrine close to the gods. You recognize one by its rectangular mud-brick footprint, flat (not pointed) top, sloping buttressed walls, and one or three long ceremonial staircases climbing the front face; the best-preserved example is the roughly 4,000-year-old Great Ziggurat of Ur in southern Iraq.

72.See a Space Launch Pad

A space launch pad is the fixed ground installation where rockets are fueled, raised vertical, and launched — recognizable by a towering open steel framework (the fixed service structure or launch tower) standing beside a flame trench and concrete platform, ringed by tall slender lightning masts and umbilical arms that swing away at liftoff, almost always set on a flat coastal stretch with wide clearance and a crawlerway leading in. The most famous example is Kennedy Space Center's Launch Complex 39A in Florida, which sent Apollo 11 to the Moon and the Space Shuttle to orbit.