Once one of the world's great cities, Cahokia was a place of religious worship, trade and mass human sacrifice before being mysteriously abandoned.

The Old Courthouse takes visitors on a captivating trip through St. Louis' timeline.

What was once a presidential estate is now an exotic menagerie and home to the Budweiser Clydesdales.

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.

Ancient burial grounds of the wealthy.

The world's largest model of our planetary system.

Sweden's "good old days" painstakingly re-created in a model village.