This long-hidden space above Westminster Abbey now displays the battle gear of the legendary King Henry V.

A subterranean relic of the Spanish Civil War hides below this picturesque park.

This historic estate on the east shore of Lake Tahoe was home to an eccentric millionaire (and his pet elephant, Mingo).

A beautiful ruin of a 14th-century Plantagenet castle built by a medieval mercenary.

One man has carved a number of natural New Mexico caves into psychedelic sandstone temples.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

This elegant neoclassical garden is a peaceful oasis in the middle of the Nepalese capital.

These crevices cut into the mountains collect the island’s main source of precious freshwater.

A moody and picturesque riverside ruin overgrown with vegetation.

This sprawling woodland estate was the brainchild of iconic American industrial designer Russel Wright.

This historic little railroad runs through some of the most beautiful scenery in Germany.

A comprehensive collection of bonsai set in a beautiful campus.

This cave was hidden for thousands of years, storing the worldly goods of ancient Native Americans.

This famous Nevada gold mine, once a hotbed of Wild West shenanigans, is now open for tours.

A gothic palace of endless stalagmites and pseudoscorpions waits within one of the world's most beautiful caves.

A midcentury ranch house hides a literal treasure trove of unique rocks and minerals.

A stretch of land where the sour-sweet vegetable is cloaked in darkness and grows so fast you can hear it crack, squeak, and pop.

A rare surviving example of a pre-WWII Japanese garden, restored after years of neglect.

A collection of the specialized tools used to construct Japan’s beautiful architecture.

All aboard the world's longest miniature railway.

Large, airy hallways hide within an impenetrable fortress that beckons urban explorers.

This tiny 1930s Art Deco airport is a beautiful remnant of a bygone era.

Romans built the world's tallest artificial waterfall in 271 BC.

This giant, 83-year-old ship elevator is an engineering feat to behold.