A swing to dangle you off the very edge.

These giant mummies are set ominously into a Peruvian cliffside and topped with real human skulls.

One of the world's tallest waterfalls wasn't revealed to the world at large until 2006.

Rising out of miles of farmland, these buttes are sometimes called the world's smallest mountain range.

Canada’s surprisingly controversial monument to Dwight Eisenhower.

A mountain pass in Bulgaria's Balkan Mountains was the site of four historic battles.

A strange egg in a mucky bog of western Ireland marks the spot of an aviation milestone.

A 6th-century stone lies at the site of the mythical battle waged between King Arthur and his nemesis Mordred.

A Bhutanese temple gifted from the isolated Himalayan kingdom is now a surprising cultural gem located at the University of Texas at El Paso.

This 15th-century island fortress later served as home to the executioners no one wanted to live near.

Bonsai trees that are up to a thousand years old.

A monument to the British doctor who connected mosquitoes to malaria.

Stunning ruins of what was once the center of one of the greatest empires in East Africa.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

A crumbling hospital from the 1850s on Roosevelt Island.

A lovers' beach, tucked below the surface of the island, provides a safe haven for romance.

On the Oregon coast there is a natural hole that seems to be draining the sea.

World's first "penitentiary," meant to be humane, drove men insane.

An exquisite tunnel of cascading flowers.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

During prohibition, corrupt city officials ran drinking dens under the streets of Downtown Los Angeles.

New York's oldest and possibly grandest keeper of books.

A museum now occupies the mansion in Samoa where the prolific Scottish writer chose to spend the last years of his life.