The largest hewn stone in history.

These crumbling Latvian forts make for some haunting seaside ruins.

A former Latvian headquarters of the brutal KGB secret police is now open as a grim reminder of their atrocities.

Buried in the Laos jungle is a sanctuary for bears that would have otherwise been milked to death by poachers.

Believed to have once stored either human remains or rice wine, thousands of mysterious stone jars lie in ruin.

A boat ride through utter darkness, lit only by headlamps, reveals an emerald green pool locals believe is sacred.

This tiered waterfall is so pretty it may cause visitors to cry tears of their own.

Time capsule of a museum, in which the Soviet Union remains alive and kicking.

Extremely isolated Silk Road caravanserai in the middle of nowhere.

Wander among the ghostly ruins of an island where civilization flourished for thousands of years.

Kuwait City's uniquely designed water towers look straight out of a retro sci-fi cityscape.

A private collection of over 30,000 ancient and modern items showcasing the beauty of Islamic calligraphy.

A symbol of the Workers' Party of North Korea.

Captured in 1968, the Cold War spy ship is the only U.S. Navy vessel being held by a foreign government.

A giant bronze monument to Kim Il-sung and Kim Jong-il is one of the most sacred sites in North Korea.

North Korea's massive "hotel of doom."

Strange sandstone canyon known as the "place broken by itself."

Life and death are on parade at the most reliably perilous site of “the Great Migration.”

Just outside of Nairobi lies a large estate surrounded by endangered Rothschild giraffes, who have been fed from the window by Mick Jagger and Walter Cronkite.

Abandoned city hidden from the world by tropical forest and isolation on the coast of Kenya.

A brilliant turquoise lake in the mountains.

World's oldest and largest space launch facility, once a secret missile testing site.

Rusting ships sit in a desert where a sea used to be.

Submerged trees jut ghost-like out of an idyllic turquoise mountain lake.