A historic neighborhood church is reborn as a psychedelic arts collective.

The country's oldest continually-operated mini golf course lies hidden in plain sight, eclipsed by one of D.C.'s most popular tourist attractions.

This lovely picnic spot featuring thunderous jet landings is an aircraft spotter’s dream.

A former major munitions plant that has been converted into a sprawling art space.

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

This methodist cemetery is slowly receding into the wilderness along a Maryland highway.

A state park that once served as an important river crossing, and now offers protected lands for endangered plants and animals.

One of the earliest and best-preserved buildings in Charles County, 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.

Home of the physician who set the leg of John Wilkes Booth after the Lincoln assassination.

The world's oldest continuously operating airport was founded by the Wright Brothers.

A mammoth pair of Civil War artillery guns abandoned out in the forest.

Once America's tallest structure, now a Baltimore landmark.

The whole world in one water tank.

Once part of a dam servicing an early 19th century grist mill, the tucked-way falls are a tricky-to-find urban oasis.

This fort down the Potomac from Washington, D.C. was once the only defensive fort protecting the capital.

Two dozen pinball games hidden away inside a most unlikely location.

Live data is transmitted from the Atlantic coast to instantly recreate the ocean waves in this fountain at the NOAA headquarters.

A haunting exhibit in a wildlife refuge center highlights threatened species and the conservation efforts needed to save them.

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

Captain John Smith thought these cliffs were amazing in 1608 but sharks thought so 20 million years before him.

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

This dig site outside D.C. is known for its exceptionally high density of baby dinosaur fossils and dinosaur eggs.

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