A gateway to a mysterious network of underground tunnels.

A series of waterfalls so massive they straddle the border of Argentina and Brazil.

This historic, palatial theater is now one of the world’s most beautiful bookstores.

One of the largest ancient geoglyphs in the world is a tall desert god used for predicting the weather.

One of Chile's most active volcanoes is riddled with beautiful caves.

A fantastical group of cliffside stairways, bridges, and twisting paths carved out of stone provide a surreal coastal hike.

This Japanese-inspired labyrinth of hot springs is hidden in a Chilean forest.

Mother Nature outdoes herself with this stunningly beautiful set of caves carved into marble.

A dangling church built over a Colombian gorge.

Folklore says this medieval fortress was plopped atop a portal to hell to trap the demons below.

These tombs were built into the side of a mountain so that ancient angels could reach the dead.

A Turkish ghost town abandoned in a population exchange with Greece.

A delightful architectural wonder awaits on a lake island in Kuala Lumpur’s oldest park.

One of the largest caverns in the world has a maw large enough to stack cathedrals in.

Holy Hindu shrine in an enormous, monkey-filled limestone cavern.

Extravagant mosque honors modern Islam.

The wing of this deserted Boeing 737 almost touches the Dunkin' Donuts next door.

A small museum full of giant effigies of Bali's demons and monsters.

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

This tiny lake temple dedicated to a water goddess seems to float on the surface.

This Balinese sea temple is thought to be guarded by the hundreds of monkeys that live around it.

This Sumatran root bridge took almost 30 years to knit itself together.

Three wildly colorful calderas top this otherworldly volcano chain.

Once home to Komodo dragons, this island dreamscape has a rare combination of white, pink, and black sand beaches.