A celebrity from the late Cretaceous period.

Rumor has it the uncarved lump behind the three famous suffragists is reserved for the first woman president.

Largest Roman Catholic church in North America.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

The national park was once a plantation estate.

Fittingly, America's museum of architecture is itself a magnificently designed old building.

A lovely aquatic park built by a one-armed Civil War veteran who made a fortune from lotuses.

A tiny piece of the Moon is embedded in this stained glass masterpiece.

Home to items never before seen by the public.

Remnants of a storybook amusement park hidden behind a strip mall.

Historic barracks utilized during both the Revolutionary War and the Civil War.

This general store has stood in the same spot for well over a century.

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

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

This bell is one of the last remnants of the lost city of Triadelphia.

A winding district gerrymandered into the shape of a mantis.

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

FDR's Art Deco hospital tower was hopelessly inefficient.

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

Once a thriving business district, this former shopping area is now an urban ghost town in the heart of the city.

This rare triple-jurisdiction drawbridge passes through Virginia, Maryland, and Washington, D.C.

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

A relic of FDR's brief foray into utopian urban planning.

One of the only memorials dedicated to journalists who died in combat.