Europe

Austria:

Rogner Bad Blumau (Bad Blumau)

Surreal Lawn-House (Frohnleiten)
Kunsthaus Graz (Graz)

Apocalypse Chapel (Klagenfurt)
Hundertwasser-Haus (Vienna)
Müllverbrennungsanlage Spittelau (Vienna)

KunstHaus Wien (Vienna)

Secession (Vienna)
Bar Rectum (Vienna)
Swarovski Kristallwelten (Wattens)

Belgium:

Dinner in the Sky (Brussels)
Hotel Tassel (Brussels)

Tower of the Apocalypse (Eben-Emael)

The house of James Ensor (Ostend)

Bosnia and Herzegovina
Sanski Most Spomenik (Sanski Most)

Bulgaria:

Rila Monastery (Rila Mountains)

Croatia:
Jasenovac monument (Jasenovac)

Czech Republik:

Sedlec Ossuary (Kutná Hora)

The Dancing House (Prague)

Denmark:

Hotel Fox (Copenhagen)
Stained-glass house (Copenhagen)

 

Finland:

Palace of dreams (Helsinki)

Hotel & Igloo Village (Saariselkä)

France:

Oak chapel (Allouville- Bellefosse)

Gainza Treehouse (Biarritz)
La Maison Picassiette (Chartres)

Le jardin de nous deux (Civrieux d'Azergues)
(Colmar)

Musée Robert Tatin (Cossé-le-Vivien)

Ferdinand Cheval's Palais Idéal (Drôme)

The house and garden of Claude Monet (Giverny)

Jardins Secrets (Haute-Savoie)
Maison Coilliot (Lille)

Lyons-satolas TGV station (Lyons)

Bubble Tent Hotel (near Marseille)
Le Cyclop (Milly-la-Forêt)
Central Nice Library (Nice)

Cunégonde et Malabar (Nice)
Les Mystères du Nautilus (Disneyland Paris)

Cafe de L'Enfer (used to be in Paris)

29 Avenue Rapp (Paris)

Quai Branly Museum (Paris)

Palais Royal Metro Station (Paris)

Sainte Chapelle (Paris)

Reconstruction of the Fouquet Boutique (Paris)

Painted house (Paris)

La maison de Celle-Qui-Peint (Pont-de-l'Etoile)
Gardens of Marqueyssac (Vézac)

Germany:

Hundertwasser-Kuchlbauer Tower (Abensberg)
AquaDom (Berlin)
Propeller Island City Lodge (Berlin)

Rettungsturm (Binz auf Rügen)

Waldspirale (Darmstadt)
Kunsthofpassage Funnel Wall (Dresden)
Neuschwanstein Castle (Hohenschwangau)

Faces along the Path (Landstuhl)

Das Junkerhaus (Lemgo)

Upside-down house (Trassenheide)

Giant Lego Bridge (Wuppertal)
Rainbow Staircase (Wuppertal)

Hungary:
Lutheran Church (Siofok)

Iceland:

Lonely house (Elliðaey)

Hallgrímskirkja - Church of Hallgrimur (Reykjavík)

Italy:

The conic "Trulli" dwellings (Apulia)

Villa Lante water gardens (Bagnaia, near Viterbo)

Park of the Monsters (Bomarzo)

Colourful tower houses on Liguria's coast
Castello di Sammezzano (Reggello)
Casina delle Civette at Villa Torlonia Park (Rome)

Cimitero dei Cappuccini (Rome)
Cave dwellings (Sassi di Matera)

Casa Fenoglio-La Fleur (Turin)

San Galgano Abbey (Tuscany)

The Tarot Gardens (Tuscany)

The Temples of Damanhur (Valchiusella)
Burano Island (near Venice) 

Lithuania:

Hill of Crosses (Šiauliai)

Macedonia:
Makedonium (Kruševo)

Netherlands:

WoZoCo Apartments (Amsterdam)

Excalibur (Groningen)
Bolwoningen (Hertogenbosch)

The Efteling (Kaatsheuvel)

Keukenhof Tulip Gardens (Lisse)
Beukelsblauw (Rotterdam)

Kubuswoningen - Cubic houses (Rotterdam)

Norway:

Igloo hotel (Alta)

Poland:

The Crooked Forest (near Gryfino)
The crooked house (Sopot)

Upside-down house (Szymbark)

Portugal:

Striped houses of Costa Nova (Costa Nova do Prado)
House of Stone (Fafe mountains)

Pena Palace (Sintra)

Livraria Lello (Porto)

Romania:

Merry Cemetary (Săpânţa)

Russia:
 (for the Asian part click here: Asia)

World's tallest log cabin (Arkhangelsk)

Monastery under the lake (Kalyazin)
Moscow metro stations (Moscow)

Spain:

Bellesguard (Barcelona)
Casa Batlló (Barcelona)
Casa Calvet (Barcelona)

Casa Milà - La Pedrera (Barcelona)

Casa Vicens (Barcelona)

Palau Güell (Barcelona)

Park Güell (Barcelona)

El Capricho (Comillas)

Dali Museum (Figueres)

Casa Navás (Reus)

Tenerife Concert Hall (Santa Cruz)
Metropol Parasol (Seville)
City of Arts and Sciences (Valencia)

Sweden:

Dragspelhuset (Glaskogen)

Homeless Experience Hotel (Göteborg)
The Mirrorcube Tree Hotel (Harads)
The original Ice Hotel (Jukkasjärvi)

Turning Torso (Malmö)

Mine- Suite (Sala)
Stockholm Metro (Stockholm)
Hotel Hackspett - Woodpecker hotel (Västerås)

Switzerland:

Residential House Vetsch (Dietikon)
Church of St John (Mogno)
Skulpturenpark (Spreitenbach)
The Blur Building (Yverdon-les-Bains)

Ukraine:

The Swallows Nest (Gaspra)
House with Chimeras (Kiev)

Tunnel of Love (Kleven)
Floating House (Krasnosilka)
Cave Monastery (Rozgirche)

Polina Rajko's house (Tsuriupinsk)

Druzhba Holiday Center Hall (Yalta)

United Kingdom:

Selfridges - Future systems (Birmingham)

Miniature Village (Bourton-on-the-Water)

The Royal Pavillion (Brighton)

The Eden project (Cornwall)

The Garden of Cosmic Speculation (Dumfries)

Kelburn Castle (Fairlie)
Harlaxton Manor (Harlaxton)

Athenaeum Hotel (London)
Craig Masson & Andrew McMinn's home (London)

The Hardy Tree (London)
Karma Taxis (London)

Zandra Rhodes' apartment (London)

The Dinosaurs of Crystal Palace (South London)

Shell Grotto (Margate)
Little retreat (Northamptonshire)

Alnwick Garden (Northumberland)

The Sage (Newcastle)

Prison Hotel Oxford Castle (Oxfordshire)

Little castle (Pitlochry)

Portmeirion
Amberley Castle Treehouse (Sussex)

A low impact Woodland Home (Wales)
La Rosa Campsite Extraordinaire (Whitby)

For countries like Turkey etc see the continent's page "Asia"