Despite violent work crews and massive delays this abandoned canal tunnel was built to last into the modern day.

An eerie, decaying ghost town destined to fade into the forest.

The remnants of a wooden-hulled fleet built and abandoned in WWI, now home to a thriving ecosystem.

This abandoned asylum was once a state of the art facility before devolving into one of the most deadly mental institutions in American history.

This free, take-a-book shop seems like a trick but isn't.

A winding district gerrymandered into the shape of a mantis.

The development and impact of electronic media showcased in a picturesque farmhouse in Maryland.

This former asylum for Black Americans is haunted by its history of violence and racism.

A faded sign from the 1920s remembers Baltimore's resistance toward banning alcohol.

A blank headstone topped with a pile of pennies marks the final resting place of the infamous assassin.

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

A small token of gratitude from freezing cold journalists who were given a warm haven while covering JFK's inauguration.

An intricately designed junk art house with four extravagant junk art cars hidden in the suburbs.

An allegorical sculpture in Maryland wears the artist’s politics on its trunk.

The shelves in the back of this thrift store are devoted to saving, not selling, retro tech.

The semi-reclaimed ruins of this canal were once part of an ambitious plan to reroute the mighty potomac.

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

This throwback amusement park is home to rides and unique storybook figures from the past.

A cave on the Maryland border where civilians took refuge during the bloodiest battle of the Civil War.

Bizarre Cavern.

A Civil War Museum with some notable medical antiques.

Crammed into a Baltimore row house is an oddities shop that sells everything from skulls to dead insects.

A historic estate packed with George Washington's heirlooms, and its own nuclear bunker.

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.