A miniature world of concrete and stone in Springfield, Ohio.

The largest ancient burial mound in Ohio.

A real flying saucer, contracted by the U.S. Air Force.

This stuffed pigeon of war had the very serious name "John Silver" until he lost a leg in battle.

The world's first aircraft factory has been hiding inside an automobile plant for almost 80 years.

Over 12,500 words are scrawled across each room of this historic plantation house and no one knows why.

This Florida sinkhole hides a rainforest-like micro-environment in its depths.

The world's largest occupied bat houses hold hundreds of thousands of flying mammals.

A beautifully detailed Victorian house designed to be easy to flee, built by a man haunted by fire.

This historic oak tree has been around for over 300 years and might last for 300 more so long as it doesn't fall apart first.