The smallest covered bridge in Maryland.

This advertisement for talcum powder was painted on the rock face and has since defied removal.

An abandoned church gets a second life as a massive beer hall and event space.

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

It's not hard to see why the historic Peabody Conservatory of Music's library has been described as a "cathedral of books."

A surprising, but overlooked example of geology in the middle of the nation’s capital.

The sci-fi villain is a little-known inhabitant of the U.S. capital's largest cathedral.

Once home to seven different roller coasters, Glen Echo has undergone many transformations since its founding in 1891.

Hidden within an idyllic suburban garden is a memorial dedicated to the victims of a terrifying spree of killings committed on U.S. soil.

Surrounded by traditional homes, this Tolkien-esque dwelling stands out on a quiet street in suburban Maryland.

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

This mighty white oak in Bethesda survived both the American Revolution and the construction of Washington D.C.'s metro red line.

The longest escalator in the Western Hemisphere takes over three minutes to ride down.

A benevolent, 16-foot-tall river dragon lives on a suburban lawn.

The wooded estate of the Forest Service employee responsible for D.C.’s cherry blossom trees.

The tallest The Church of Jesus Christ of Latter-day Saints temple in the world soars above the Beltway.

Built in 1945, this historic train station has a new lease on life with its baggage area serving as an event space.

A tribute to the beloved, kind-hearted "homeless mayor" of Silver Spring.

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

A girls' boarding school inspired by the Chicago World's Fair, once abandoned, now restored to strange and scenic glory.

Brain collection and database that narrows the gap between man and animal.

An astounding collection of medical specimens, including bits of President Lincoln.

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

Chilly air billows out from the entrance of an abandoned mine on a steep hillside, providing a refuge for Ice Age fauna and flora.