This tunnel entrance is built to resemble a grand castle but no one is quite sure why.

A remarkable geological formation resembling a forest made of stone.

A lush desert oasis in the shape of a narrow crescent.

A glacier pocked with ice caves and surrounded by rainforests.

A modern version of the stone cairns built by the Inuit.

The Avenue of Mausolea is a series of grand palatial tombs.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

This peaceful sanctuary is one of the oldest Buddhist temples in Colombo.

The huge golden reliquary of a testicle-smashing saint.

Hanging over one of Japan's "hidden valleys," these vine bridges must be remade every three years.

This quiet park's strange sedimentary spires were named after Kodak's color film.

This picturesque medieval monastery guards a small trove of historic treasures.

Hundreds of stone stairs and a winding medieval bridge connect this haunting Spanish island to the mainland.

The enormous isokinetic structure hangs within a science center in Estonia.

Rising from the sea like a stone monster.

This chicken coop pays homage to a classic architectural style made famous throughout the southern United States.

A tunnel with windows, so you don't miss out on the impressive views.

A fiery crater has been burning in the Karakum Desert since 1971.

A rare cluster of alien-like plants grows along a dusty highway.

This statue dedicated to the story of a Flemish boy and his dog was relatively obscure in Belgium, but a cult sensation in Japan.

About as hidden as can be, this specialty coffee shop is wedged between multi-story buildings at the end of a dark, skinny alleyway in Seoul.

Various forms of phallic art decorate this hill in commemoration of legendary local tragedy.

A theme park made of glass, from the gleaming books on the shelves to the crystal fish in the mirror lake.

Natural rock water slides hidden in the remote forests of northern Idaho.