The phenomenon of the Hill of Crosses in northern Lithuania began when people started leaving crosses there hundreds of years ago – and continues to this day. These photos of a hill covered in crosses show the amazing sight it has become. Photo: In 1831 an unsuccessful uprising against the Russian czar left many rebels dead. Relatives of the dead rebels, with no bodies to bury, instead left crosses, according to the Daily Mail. (Photo by Richard Gardner/Rex USA)

Hot Tub Cinema is an experience like no other. Combining relaxing hot tubs, great films and amazing spaces, it is a luxurious event that celebrates film in a fun and engaging way. Attendees can purchase whole tubs to share with friends or buy individual tickets to share with fellow hot tubbers. The tubs are cleaned, refilled and heated before every show. Popping-up throughout the year in London and around the UK, Hot Tub Cinema is also preparing to tour internationally in the near future. During the summer, we takeover rooftops in central London with astounding views across the city's inimitable skyline. For the autumn/winter we move indoors to continue the fun hidden away from the unpredictable weather.

People appear dangling as a large-scale installation art piece by Leandro Erlich, named “Dalston House”, in London, England. Part of the “Beyond Barbican” summer series of events, the interactive installation is a full facade of a late nineteenth-century Victorian terraced house built on the ground with a large mirror above it to reflect people as to appear dangling from the structure. (Photo by Dan Dennison)

Ethnic Cham Muslim people pass the time near their boats on banks of Mekong river in Phnom Penh July 29, 2013. About 100 ethnic Cham families, made up of nomads and fishermen without houses or land who arrived at the Cambodian capital in search of better lives, live on their small boats on a peninsula where the Mekong and Tonle Sap rivers meet, just opposite the city's centre. The community has been forced to move several times from their locations in Phnom Penh as the land becomes more valuable. They fear that their current home, just behind a new luxurious hotel under construction at the Chroy Changva district is only temporary and that they would have to move again soon. (Photo by Damir Sagolj/Reuters)

Isabel Schmalenbach, an environmental scientist with the Helgoland Biological Institute (Biologische Anstalt Helgoland), part of the Alfred Wegener Institute for Polar and Marine Research, holds a one-year old baby European lobster (Homarus gammarus) raised at the institute on August 3, 2013 on Helgoland Island, Germany. Later in the day Schmalenbach and her colleagues released a total of 415 one-year old lobsters into the North Sea as part of an effort to repopulate the lobster population around Helgoland (also called Heligoland). In the 19th century local fishermen caught up to 80,000 lobsters a year in the surrounding waters, combined with the heavy allied bombing of the island during and after World War II, as well as other environmental factors, decimated the lobster population. (Photo by Sean Gallup)

Among the fish populations that could be harmed by the Xayaburi dam in Laos is the critically endangered Mekong giant catfish, considered by the Guinness Book of World Records to be the world’s largest freshwater fish. The fish, which grows to 650 pounds and about 10 feet long, is only found in the Mekong River. It is migratory, moving between downstream habitats in Cambodia upstream to northern Thailand and Laos each year to spawn. Some experts fear the Xayaburi dam could block the migration and drive the giant catfish to extinction. (Photo by Courtesy of Zeb Hogan/University of Nevada, Reno)