Once the center of a thriving early Black community called Martinsburg.

The ruins of an old mill lie in a small ravine along a hiking trail near Little Seneca Creek.

Dating to 1793, this is the oldest building in Poolesville.

Using a massive antenna made up of five miles of wire, two scientists tuned into organic radio waves from the planet Jupiter.

The oldest military monument in the United States.

This statue honors the author's groundbreaking family story.

The rock on which Moll Dyer was found frozen to death is said to still bear her handprint.

This hidden treasure provides a charming access point along the south side of Baker Park.

First built around 1848, this bridge was destroyed by arson, but original timbers are included in the replacement.

The ruins of an 18th-century mansion that was once named "Mistake" by the man who had it built.

Washed out by the Johnstown Flood in 1889, the surviving portion of the original two-span bridge now resides at Fishing Creek.

Built in 1815, the stabilized ruins of the grist mill and sawmill are now gated, but interpretive displays on the features and functions of the mill preserve its history.

One of the oldest standing structures in Montgomery County, Maryland.

Unannounced visitors are now welcome at the site of the largest Prohibition-era bootlegging operation in the region.

The hidden ruins of a mill that is linked to an attempt to assassinate the vice president of the United States.

The rooster who crossed the road lives on forever in Takoma Park, Maryland.

The 72-foot giant escaped confinement in a large patch of mulch only to be reburied in the sandy shores of the Potomac River.

Remains of a historic fountain that was mysteriously lost in the demolition of a D.C. traffic circle.

At this former Prohibition speakeasy, electric birds signaled the arrival of hooch.

Dogs, cats, horses, monkeys, frogs, and fish are laid to rest at the second-oldest pet cemetery in the U.S.

This ruined quarry once produced the distinctive red sandstone used for construction projects in Washington, D.C.

A pre-Industrial Age iron furnace and the site of a nearly-forgotten piece of Black history.

A Civil War Museum with some notable medical antiques.

The final resting place of the tragic king and queen of the Jazz Age is tucked away in a small Maryland graveyard.