This natural wonderland is a unique chance to explore a Carolina bay, a mysterious geological formation of unknown origin.

An unfinished rail tunnel that has since been used to house cheese and bats.

San Francisco's newly reopened hands-on science museum.

This naturally heated mountainous creek has created a group of neon blue pools of potentially deadly boiling water.

An apocalyptic seismic event creates a deadly chain reaction that ends with a 6-mile long lake developing within weeks.

Aqueducts have dramatically changed this old lake, now home to tufa towers and its very own species of tiny brine shrimp.

1513 Turkish world map, full of European state secrets and snarky commentary.

Largest island in the Baltic Sea experiences such idyllic weather that roses bloom in the middle of December.

Twelve natural mummies are displayed in the crypt of this former monastery school.

A disquieting Aztec sculpture displays hundreds of stone skulls representing the victims of human sacrifice.

A scientific repository of goiters, boils and other ailments throughout Mexican history.

Explore the atmospheric ruins of an abandoned convent in the dense forests of Mexico's first national park.

What killed this humpback whale is a mystery, but its remains have become legendary.

A literally moving statue of stacked metal giants just continually trying (and failing) to find love.

The ornate miniature mansions were built for Istanbul's feathered residents.

The home of pigs, snakes, chameleons, and the alleged largest bunny in the United States.

The semi-reclaimed ruins of this canal were once part of an ambitious plan to reroute the mighty potomac.

One of the last active volcanoes on the Eastern seaboard.

This maze-like slot canyon is a unique gem within an already fascinating geological area.

The highest point in Virginia can only be reached by passing through ponies and flowers.

Mysterious Incan ruins on a tiny island in Lake Titicaca.

A lake in the middle of the tundra of Quebec is said to be the purest freshwater lake on Earth.

The Roman Emperor's lost summer home and grotto full of enormous sculptures sit along the Italian seashore.

Erotic art covers the walls of the largest ancient pleasure palace.