A Civil War fort in the middle of Washington, D.C. has been swallowed by a forest.

The headquarters of the Audubon Naturalist Society is a small slice of heaven for nature lovers.

Baltimore's classic clock tower was once topped by a rotating, 20-ton medicine bottle.

Historic home of America's sweetheart sharpshooter, Annie Oakley.

Explore the legends surrounding these mythical sea creatures inside this museum.

Fascinating museum dedicated to the under-appreciated medical history of urology features some wince-inducing devices.

A Civil War Museum with some notable medical antiques.

The ruins of this long-abandoned unsuccessful gold mine can still be found.

An eerie, abandoned military base engulfed by nature and graffiti is now home to a local park.

A priceless collection of the Nation's cryptologic history.

A hidden alley in urban Baltimore is a haven for graffiti artists.