A 1,215-foot tunnel transports pedestrians beneath the River Thames.

London's smallest police station is barely the size of a phone booth.

Hear the quietest sound from across the dome.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

One part local history, 99 parts gruesome haunted house.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

A gruesome memorial for those lost in this area during the Khmer Rouge genocide.

This collection of reclaimed landmines acts as both an exhibition of their deadly history and as a shelter for children affected by them.

Khmer Rouge's high security prison.

Built by King Norodom to honor his late father.

5,000 skulls in memorial to those killed by the Khmer Rouge.

A battle between nature and architecture in the Cambodian jungle.

Bangkok celebrated its shifting monarchy with a militaristic homage to democracy.

The golden Buddha statue at the Wat Muang Monastery is the tallest in Thailand, and the ninth-tallest in the world.

This elephant kraal is the only one remaining in Thailand, dating back to the 16th century when these massive mammals were integral players in war and trade.

This $62 million dollar temple was erected to house one little dental fragment of religious history.

The largest pool at its elevation sits on top of one of the most expensive resorts in the world.

Once the private home of China’s most legendary tycoon, getting inside this stunning mansion no longer requires an elite pedigree or acts of daring.

Abandoned limestone cave was once a sacred place of worship.

Exotic, erotic, and esoteric, one artist's live-in Bali gallery brings a splash of color and madness to its surroundings.

Hindu temple of the dead home to hundreds of long-tailed macaques.

Time has stopped at the house where Gandhi died.

The world's largest secondhand book market is a haven for bibliophiles and bargain hunters.