T-Centralen Metro Station, Stockholm, Stockholm County, Sweden

Solna Centrum Metro Station, Stockholm, Stockholm County, Sweden

Romania, Transylvania, Cluj-Napoca. The 42 metre deep, 50 metre wide and 80 metre long Rudolf Mine at Salina Turda - a historic salt mine disused since the early 20th Century and converted into a fut...

Romania, Transylvania, Cluj-Napoca. An aerial view of the Terezia Mine at Salina Turda - a historic salt mine disused since the early 20th Century and converted into a futuristic theme park. Open to t...

Romania, Transylvania, Cluj-Napoca. The 42 metre deep, 50 metre wide and 80 metre long Rudolf Mine at Salina Turda - a historic salt mine disused since the early 20th Century and converted into a fut...

Baker Street Underground station, London, England, UK

North Korea, Pyongyang. A guard seeing off a train at Yonggwang ('Glory') metro station, on the Chollima line.

Evening at the Metro stop Saint Michel in the Latin Quarter, Paris, France

Europe, Germany, Berlin, modern subway station - moving train pulling into the station

United Kingdom, England, London, Piccadilly Circus, Piccadilly underground station

Oak wine barrels and stainless steel fermentation tanks at underground aging wine cellar in Haras de Pirque winery, Pirque, Maipo Valley, Cordillera Province, Santiago Metropolitan Region, Chile

Oak wine barrels at underground aging wine cellar in Haras de Pirque winery, Pirque, Maipo Valley, Cordillera Province, Santiago Metropolitan Region, Chile

Oak wine barrels at underground aging wine cellar in El Principal winery, Pirque, Maipo Valley, Cordillera Province, Santiago Metropolitan Region, Chile

South America, Colombia, Cundinamarca, Zipaquira. Chapel in the salt cathedral of Zipaquira - an underground Catholic church built within the tunnels of a salt mine

Radhuset metro station, Stockholm, Stockholm County, Sweden

Solna Centrum Metro Station, Stockholm, Stockholm County, Sweden

T-Centralen Metro Station, Stockholm, Stockholm County, Sweden

Stadion Metro Station, Stockholm, Stockholm County, Sweden

Mexico, Valladolid. Suytun Cenote

Europe, UK, England, London, Westminster, interior of Westminster Underground railway station, architects: Michael Hopkins & Partners, completed 1999, no people

United Kingdom, England, London, interior of a passenger concourse on the London Underground

Ukraine, Kyiv, Arsenalna Metro Station, Currently The Deepest Station In The World, Part Of The Kyiv Metro Line, Chandelier Lighting

Ukraine, Kyiv, Arsenalna Metro Station Escalators, Currently The Deepest Station In The World, Part Of The Kyiv Metro Line

Sweden, Stockholm, Stockhom Underground Metro, Tekniska Hogskolan Station, escalator lit with colored lights

Sweden, Stockholm, Stockhom Underground Metro, Tekniska Hogskolan Station

Men looking at artwork and paintings on rocks, Solna Centrum metro station, Stockholm, Sweden

Überseequartier station on U4 U-Bahn line, HafenCity, Hamburg, Germany

HafenCity Universität station on U4 U-Bahn line, HafenCity, Hamburg, Germany

Bülowstrasse is a Berlin U-Bahn station located on the U 2 in the Schöneberg district. It opened in 1902 on the western branch of Berlin's first U-Bahn line. Like the street, the station is named afte...

UK, England, London, West End, Tottenham Court Road Underground Station

Salt Cathedral, interior, Zipaquira, Cundinamarca Department, Colombia

Salt Cathedral, interior, Zipaquira, Cundinamarca Department, Colombia

Romania, Transylvania, Cluj-Napoca. An aerial view of the Terezia Mine at Salina Turda - a historic salt mine disused since the early 20th Century and converted into a futuristic theme park. Open to t...

Romania, Transylvania, Cluj-Napoca. The 42 metre deep, 50 metre wide and 80 metre long Rudolf Mine at Salina Turda - a historic salt mine disused since the early 20th Century and converted into a fut...

Romania, Transylvania, Cluj-Napoca. The bridge to the boating lake in the Terezia Mine at Salina Turda - a historic salt mine disused since the early 20th Century and converted into a futuristic theme...

Romania, Transylvania, Cluj-Napoca. The boating lake in the Terezia Mine at Salina Turda - a historic salt mine disused since the early 20th Century and converted into a futuristic theme park. Open to...

Portugal, Lisbon. Escalators and the colorful decorations at Olaias subway station.

Minsk metro, Minsk, Belarus

Minsk metro, Minsk, Belarus

Minsk metro, Minsk, Belarus