Internally displaced Syrian children stand at the entrance of their makeshift shelter that is an underground cave in Om al-Seer, southern Idlib countryside, Syria December 26, 2015. (Photo by Khalil Ashawi/Reuters)
A mother and her daughter paddle during a Stand Up Paddle (SUP) race of the Alpine Lakes Tour, on Europe's biggest underground lake, in St-Leonard, Switzerland, March 10, 2018. SUP is an offshoot of surfing that originated in Hawaii. Unlike traditional surfing where the rider sits until a wave comes, stand up paddle boarders stand on their boards and use a paddle to propel themselves through the water. (Photo by Denis Balibouse/Reuters)
Partially constructed notched burial plots are seen at the construction site of an underground tunnel designated for traditional Jewish burial at the Givat Shaul cemetery, on May 14, 2015, in Jerusalem, Israel. Underground cemetery being built by the Israeli Burial Society in Jerusalem due to a decrease in available land for traditional Jewish burials. (Photo by David Vaaknin/The Washington Post)
The Puerto Princesa Subterranean River National Park is located about 50 kilometres (30 mi) north of the city centre of Puerto Princesa, Palawan, Philippines. The river is also called Puerto Princesa Underground River. The national park is located in the Saint Paul Mountain Range on the northern coast of the island. It is bordered by St. Paul Bay to the north and the Babuyan River to the east. The City Government of Puerto Princesa has managed the National Park since 1992. The park is also known as St. Paul's Subterranean River National Park, or St. Paul Underground River. The entrance to the Subterranean River is a short hike from the town of Sabang.
Jim and Jamie Dutcher spent six years in Idaho in a tent within the world’s largest wolf enclosure in order to observe and document the behavior of these wild animals. They got really close to the wolves and made many unique photos of wolves in their natural habitat.
Actors from the Israeli theatre group Orto-Da perform during their show titled “Stones”, at a theatre in Tel Aviv March 10, 2015. Inspired by Nathan Rapoport's Warsaw Ghetto Uprising Monument, the play tells a story from the point of view of the sculptures in the monument. (Photo by Amir Cohen/Reuters)
The Bajau people of Malaysia live their lives completely at sea, living in wooden huts and spending their days fishing. Sailing over crystal clear waters, the Bajau people of Malaysia live their lives almost entirely at sea. Photographer Ng Choo Kia joined the Bajau people on their pirogues, which are long narrow canoes made from single tree trunks, and documented their daily life in a series of pictures. (Photo by Ng Choo Kia/Hotspot Media/SIPA Press)
Stunning silhouettes under European cities reveal the size and splendor of the continent’s urban foundations. Photographer and content-manager Anna Arinova, 28, from Moscow, captured the awe-inspiring labyrinths in Russia and Germany. Here: Regenwurmlager, Poland. The Regenwurmlager is an extensive underground fortification area constructed by Germany in 1920s-1940s, now in western Poland, near the city of Międzyrzecz. (Photo by Anna Arinova/Caters News)