 | Oak House MuseumOrt · Birmingham | Tony Hisgett from Birmingham, UK | CC BY 2.0 | Original ↗ |
 | Oakland Aviation MuseumOrt · Oakland | Bill Larkins | CC BY-SA 2.0 | Original ↗ |
 | Oakland Harbor LightOrt · Oakland | United States Coast Guard | Public domain | Original ↗ |
 | Oakland Public SchoolOrt · Pittsburgh | Lee Paxton | CC BY-SA 4.0 | Original ↗ |
 | Oaklands Sugar MillOrt · Brisbane | Heritage branch staff | CC BY 3.0 | Original ↗ |
 | Oaks Union DepotOrt · Saint Paul | McGhiever | CC BY-SA 4.0 | Original ↗ |
 | Oak TowerOrt · Kansas City | Charvex | Public domain | Original ↗ |
 | OakwalOrt · Brisbane | Shiftchange | CC0 | Original ↗ |
 | Oakwell HallOrt · Bradford | Nigel Homer | CC BY-SA 2.0 | Original ↗ |
| Oakwell Hall Country ParkOrt · Bradford | Nigel Homer | CC BY-SA 2.0 | Original ↗ |
 | Oaky GroveOrt · Raleigh | Nicholas Oren Rawlings | CC BY-SA 3.0 | Original ↗ |
 | OAP TowerOrt · Osaka | J o | CC BY-SA 3.0 | Original ↗ |
 | Oatland Island Education CenterOrt · Savannah | Michael Rivera | CC BY-SA 4.0 | Original ↗ |
 | Obecná školaOrt · Prag | Petr Vilgus | CC BY-SA 3.0 | Original ↗ |
 | ObeliscoOrt · A Coruña | Fernando Losada Rodríguez | CC BY-SA 4.0 | Original ↗ |
 | Obelisco AgonaleOrt · Rom | Wolfgang Moroder | CC BY-SA 3.0 | Original ↗ |
 | Obelisco a los Niños HéroesOrt · Mexiko-Stadt | https://secure.flickr.com/photos/rutlo/ | CC BY 2.0 | Original ↗ |
 | Obelisco de DeliciasOrt · Madrid | Malopez 21 | CC BY-SA 4.0 | Original ↗ |
 | Obelisco de la CajaOrt · Madrid | Guimir | Public domain | Original ↗ |
 | Obelisco dell'ImmacolataOrt · Neapel | black_friction | CC BY-SA 2.0 | Original ↗ |
 | Obelisco di MarconiOrt · Rom | Blackcat | CC BY-SA 3.0 | Original ↗ |
 | Obelisco di San DomenicoOrt · Neapel | Giuseppe Guida | CC BY-SA 2.0 | Original ↗ |
 | Obelisco di San GennaroOrt · Neapel | Berthold Werner | CC BY-SA 3.0 | Original ↗ |
 | Obelisco EsquilinoOrt · Rom | PubblicUsername | CC BY 4.0 | Original ↗ |
 | Obelisco EuropaOrt · Saragossa | Juanedc from Zaragoza, España | CC BY 2.0 | Original ↗ |
 | Obelisco FlaminioOrt · Rom | Apaleutos25 | CC BY-SA 4.0 | Original ↗ |
 | Obelisco FlaminioOrt · Rom | Jorge Manriquez P. | CC BY-SA 3.0 | Original ↗ |
 | Obelisco FlaminioOrt · Rom | Michael Haupt | CC BY 3.0 | Original ↗ |
 | Obelisco FlaminioOrt · Rom | daryl_mitchell from Saskatoon, Saskatchewan, Canada | CC BY-SA 2.0 | Original ↗ |
 | Obelisco LateranoOrt · Rom | unbekannt | CC BY-SA 3.0 | Original ↗ |
 | Obelisco MilleniumOrt · A Coruña | Fernando Losada Rodríguez | CC BY-SA 4.0 | Original ↗ |
 | Obelisco QuirinaleOrt · Rom | Mister No | CC BY 3.0 | Original ↗ |
 | Obelisco QuirinaleOrt · Rom | Paolo Monti | CC BY-SA 4.0 | Original ↗ |
 | Obelisco QuirinaleOrt · Rom | jeffwarder | CC BY-SA 3.0 | Original ↗ |
 | Obelisco QuirinaleOrt · Rom | Diego Baglieri | CC BY-SA 4.0 | Original ↗ |
 | Obelisco SallustianoOrt · Rom | SonyGM | CC BY 4.0 | Original ↗ |
 | Obelisco VaticanoOrt · Rom | Jebulon | CC0 | Original ↗ |
 | ObeliskOrt · Berlin | OTFW , Berlin | CC BY-SA 3.0 | Original ↗ |
 | ObeliskOrt · Triest | Twice25 & Rinina25 | CC BY 2.5 | Original ↗ |
 | Obelisk of DogaliOrt · Rom | unbekannt | Public domain | Original ↗ |
 | Obélisque de LouxorOrt · Paris | ZeusUpsistos | CC BY-SA 4.0 | Original ↗ |
 | Obélisque de MazarguesOrt · Marseille | maarjaara | CC BY 2.0 | Original ↗ |
 | Oberes BrunnenmeisterhausOrt · Augsburg | Neitram | CC BY-SA 4.0 | Original ↗ |
 | Oberlandesgericht KölnOrt · Köln | Unknown authorUnknown author | Public domain | Original ↗ |
 | ObernstrasseOrt · Bremen | Jürgen Howaldt | CC BY-SA 2.0 de | Original ↗ |
 | ObertorOrt · Düsseldorf | Käthe u. Bernd Limburg | CC BY-SA 3.0 de | Original ↗ |
 | Obispado, Mty. N.L.Ort · Monterrey | Brendablue77 | CC BY-SA 3.0 | Original ↗ |
 | Obóz przy ul. Przemysłowej w ŁodziOrt · Łódź | Archiwum Fotograficzne Stefana Bałuka | Public domain | Original ↗ |
 | Obřadní síňOrt · Prag | Jorge Royan | CC BY-SA 3.0 | Original ↗ |
 | Obřanský Most , BrnoOrt · Brünn | MIGORMCZ | CC BY-SA 4.0 | Original ↗ |
 | Obrero Mundial 383Ort · Mexiko-Stadt | Tbhotch | CC BY-SA 4.0 | Original ↗ |
 | O'Brien InstituteOrt · Dublin | Smirkybec | CC BY-SA 4.0 | Original ↗ |
 | Obrońcow WybrzeźaOrt · Danzig | Panek | CC BY-SA 4.0 | Original ↗ |
 | Observatoire de la CapitaleOrt · Québec | Jeangagnon | CC BY-SA 3.0 | Original ↗ |
 | Observatoire de Paris - PSLOrt · Paris | Pline | CC BY-SA 3.0 | Original ↗ |
 | Observatoire Panoramique de la Tour MontparnasseOrt · Paris | User:Thbz | CC BY-SA 3.0 | Original ↗ |
 | observatorijas iela 7Ort · Riga | Olgerts V | CC BY-SA 4.0 | Original ↗ |
 | Observatorul Regal Din GreenwichOrt · London | unbekannt | CC BY-SA 3.0 | Original ↗ |
 | Observatory Circle (Washington, D.C.)Ort · Washington | runneralan2004 | CC BY 2.0 | Original ↗ |
 | Óbudai GázgyárOrt · Budapest | dino | CC BY 2.5 hu | Original ↗ |
 | Óbudai MúzeumOrt · Budapest | Tacsipacsi | CC0 | Original ↗ |
 | Occidental Life BuildingOrt · Albuquerque | Camerafiend | CC BY-SA 3.0 | Original ↗ |
 | Occidental Life Insurance Company BuildingOrt · Raleigh | Nyttend | Public domain | Original ↗ |
 | Ocean Center ApartmentsOrt · Long Beach | Eric Fredericks from Rancho Cordova, CA, United States | CC BY-SA 2.0 | Original ↗ |
 | Oceanic 2000Ort · Acapulco | Mitrush | CC BY-SA 3.0 | Original ↗ |
 | Oceanwide Center, San FranciscoOrt · San Francisco | Eric in SF | CC BY-SA 4.0 | Original ↗ |
 | O'connell CenterOrt · Gainesville | DouglasGreen | CC BY 2.0 | Original ↗ |
 | O'Connell MonumentOrt · Dublin | Rodhullandemu | CC BY-SA 4.0 | Original ↗ |
 | O'Connell TowerOrt · Dublin | William Murphy from Dublin, Ireland | CC BY-SA 2.0 | Original ↗ |
 | Octagon House (Columbus, Georgia)Ort · Columbus | Unknown authorUnknown author | Public domain | Original ↗ |
 | Octavia HouseOrt · London | Thomas Nugent | CC BY-SA 2.0 | Original ↗ |
 | Odaiba Retro MuseumOrt · Tokio | Kakidai | CC BY-SA 4.0 | Original ↗ |
 | Odd Empire FellowsOrt · Raleigh | FoxDon | CC BY-SA 3.0 | Original ↗ |
 | Odd Fellows BuildingOrt · Portland | M.O. Stevens | CC BY-SA 3.0 | Original ↗ |
 | Odd Fellows HallOrt · Baltimore | Smallbones | CC0 | Original ↗ |
 | Odd Fellows Temple (Lexington, Kentucky)Ort · Lexington | Publichall | CC BY-SA 3.0 | Original ↗ |
 | Odell S Williams Now & Then African American MuseumOrt · Baton Rouge | Blair | CC BY-SA 4.0 | Original ↗ |
 | Odengatan 90Ort · Stockholm | Holger.Ellgaard | CC BY-SA 3.0 | Original ↗ |
 | Odeon of AgrippaOrt · Athen | Janmad | CC BY-SA 4.0 | Original ↗ |
 | Odeon of LyonOrt · Lyon | Pymouss | CC BY-SA 4.0 | Original ↗ |
 | OdeonsplatzOrt · München | Diego Delso | CC BY-SA 3.0 | Original ↗ |
 | Odesa Museum of Western and Eastern ArtOrt · Odessa | Hwyrd | CC BY-SA 4.0 | Original ↗ |
 | Odesa Numismatic MuseumOrt · Odessa | Федченко Владислав Володимирович | CC BY-SA 3.0 | Original ↗ |
 | Odessa WharfOrt · London | Cmd36 | CC0 | Original ↗ |
 | Odeta TerasOrt · Prag | JiriMatejicek | CC BY-SA 3.0 | Original ↗ |
 | Ode to Marten ToonderOrt · Rotterdam | Sandra Fauconnier | CC BY 4.0 | Original ↗ |
 | OdwachOrt · Posen | unbekannt | CC BY-SA 3.0 | Original ↗ |
 | Odysseum KolnOrt · Köln | Raimond Spekking | CC BY-SA 4.0 | Original ↗ |
 | OerlikonOrt · Zürich | OpenCatMap | CC BY-SA 4.0 | Original ↗ |
| Oerlikon ONEOrt · Zürich | OpenCatMap | CC BY-SA 4.0 | Original ↗ |
 | Ófalu AltdorfOrt · Budapest | Vince | CC BY-SA 4.0 | Original ↗ |
 | Öffentliche Bedürfnisanstalt am GrabenOrt · Wien | GuentherZ | CC BY 3.0 | Original ↗ |
 | Office of the World BankOrt · London | unbekannt | CC BY-SA 3.0 | Original ↗ |
 | Ogden Museum of Southern ArtOrt · New Orleans | Infrogmation of New Orleans | CC BY-SA 3.0 | Original ↗ |
 | Oglethorpe MonumentOrt · Savannah | Roman Eugeniusz | CC BY-SA 3.0 | Original ↗ |
 | Ogontz Hall ApartmentsOrt · Philadelphia | Smallbones | Public domain | Original ↗ |
 | OgrodowaOrt · Posen | MOs810 | CC BY-SA 4.0 | Original ↗ |
 | O'Hanlon BuildingOrt · Winston-Salem | Jeff Skidmore | CC BY-SA 3.0 | Original ↗ |
 | O. Henry house museumOrt · San Antonio | Larry D. Moore | CC BY 4.0 | Original ↗ |
 | O. Henry MuseumOrt · Austin | Daderot | CC0 | Original ↗ |