The Sydney Skyline is seen before the lights are switched off for Earth Hour on March 26, 2011 in Sydney, Australia. Earth Hour encourages individuals around the world to turn off their lights for one hour at 20:30 local time on March 26, 2011 to take a stand against climate change. The largest Earth Hour was in 2010 when 128 countries participated.

Workers polish a snow sculpture ahead of the 16th Harbin Ice and Snow World in Harbin, Heilongjiang province, December 22, 2014. The 16th Harbin Ice and Snow World will be officially opened on January 5, 2015. (Photo by Reuters/Stringer)

The amazing gallery shows parts of London shot from above – and the views are breathtaking. Jason Hawkes, an aerial photographer from Reading, England, captured the images over the past six months while flying in AS355 helicopters. Here: The city of London at dusk. (Photo by Jason Hawkes/Caters News Agency)

Newly-wed couples attend their group wedding ceremony which was held as part of the Harbin International Ice and Snow Festival in the northern city of Harbin, Heilongjiang province January 6, 2016. As many as 15 couples attend this mass wedding ceremony. (Photo by Aly Song/Reuters)

The television tower is pictured in Berlin, Germany, May 29, 2016. (Photo by Hannibal Hanschke/Reuters)

From Manhattan and Brooklyn's trendiest neighborhoods to the far-flung edges of theouter boroughs, Will Ellis has spent the last three years photographing and researching the lost and lonely corners of the United States' most populous city. His photo book Abandoned NYC is packed with 150 color images of sixteen of New York's most beautiful and mysterious abandoned spaces, paired with detailed essays on the fascinating history of these forgotten sites. Here: Letchworth Village is located just an hour's drive from NYC in Thiells, NY. It was founded in 1912 to house the city's developmentally disabled as a ”state institution for the epileptic and feeble-minded”. (Photo by Will Ellis)

From towering elephants to tiny insects, photographers will be offering a rare insight into the natural world at this year’s Wildscreen Photography Festival 2014. The festival, formerly known as WildPhotos, is the UK’s largest wildlife photography show. The Wildscreen Photography Festival 2014 will be taking place between 24-26 October at London’s Royal Geographical Society. (Photo by Sam Hobson/Wildscreen Photography Festival 2014)

A woman takes pictures with her mobile phone at a building, which is made by half of a replica of the Qinian Hall of the Temple of the Heaven (R) and half of a western building, at a studio for productions of films and television shows on the outskirts of Shijiazhuang, Hebei province, China, December 3, 2015. (Photo by Reuters/Stringer)