The only structure left with direct ties to the Salem witchcraft trials of 1692.

Make your reservation to have coffee with some kitties.

An old vending machine serves up unpredictable beverages from its seemingly magical insides.

The world's largest collection of mechanical puzzles is a cornucopia of analog bafflers.

The world's longest known cave system.

These azure waters were thought to lead to the Mayan Underworld.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

Every equinox this Maya pyramid puts on a spooky ancient light show.

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.

An underground city of salt.

The ghostly remains of an accidental sea.

This former small town was destroyed not by the motor oil it sprayed the ground with but by the toxic waste that was added.

Toxic waste disaster that founded the Superfund program.

A take-out restaurant that only serves cuisine from countries with which the United States is in conflict.

A cave on the Maryland border where civilians took refuge during the bloodiest battle of the Civil War.

Bizarre Cavern.

These tourist trap caverns are said to be the former home of a legendary Pennsylvania Hermit.

This lush forest valley was once mined for lumber to the extent that it was once nicknamed "The Pennsylvania Desert."

This modern monument to pagan belief looks like it was transported straight from ancient times.

This mountain fissure hides a secret path to a secluded mossy grotto within the rock itself.

This replica Viking village was created for a film that was never shot and is now open to visitors.

Walk in the footsteps of the gods and straddle two tectonic plates.

Three million year old fossils are exposed for all to see on this Icelandic shore.

The most powerful waterfall in all of Europe.