Built by the patriotic residents of Boonsboro in a single day.

This scenic Maryland park was the site of one of the worst prison camps of the Civil War.

This massive swimming pool is the high tech home to the human-powered submarine races.

A remarkable time capsule of American manufacturing deep in Maryland coal country.

A collection of artifacts from Maryland's maritime past.

The origin of the Nixon tapes is rooted in technological incompetence as much as secrecy.

This public baseball field is a beloved remainder from of one of the most historic stadiums in the country.

Detroit’s downtown castle is one of the oldest structures in the city.

This empty Detroit high school was too expensive to maintain or destroy.

This shallow cave got its name from copious amount of human bones found inside.

Legs Inn provides Polish food, a cornucopia of Native American artwork, wood carvings, and mounted deer heads.

The concrete shell of an industry giant remains as a playground for graffiti artists, auto scrappers, and paintball warriors.

A subterranean world of tunnels links several buildings of this rare 19th-century asylum.

A popular place to pick up prehistoric coral fossils from the time when Michigan was an ocean.

Turnip-shaped island just off the Michigan shore in Lake Huron.