The enormous 250-room Vanderbilt mansion conceals hidden doors and secret passageways.

This bridge is haunted by the ghost of a distraught mother.

From golden eagles to peregrine falcons, this rehabilitation and education center is a haven for birds of prey.

These otherworldly caverns form Earth's oldest known cave system.

The widest natural waterfall in Estonia is a sight to see in all seasons.

Performers, intricate sets, and a real speakeasy tell the story of the 18th Amendment.

A mysterious monument meant to be a guide into "an Age of Reason" was destroyed after an apparent bombing.

The oldest bridge in South Carolina may have been designed by the same man who created the Washington Monument.

Who needs fancy modern water slides when this giant North Carolina rock works just as well?

A curious whirlpool formation supposedly capable of entangling or engulfing branches, tree trunks, or whole rafts full of hapless tourists.