An eerily abandoned stone tower is all that remains of a demolished dam on Cape Fear River.

This sprawling museum holds one man's giant collection of real tanks.

This research center for rare prosimians is studying how they sleep to help prolong human life.

Ruins of an American Civil War iron forge still survive today.

A sculptor's dream castle turned fantastical ruin.

This bright yellow relic is the final survivor of a short burst of seashell-shaped petrol pumps.

Every drop of D.C. tap water flows through this old waterworks.

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

The famous abolitionist’s preserved estate is one of Washington's finest monuments to its great Black citizens.

Enormous piles of historically significant stones, dumped by Congress in a forest, and abandoned for 60 years.

A Civil War fort in the middle of Washington, D.C. has been swallowed by a forest.

One of the dwarven trees dates back to 1625 and survived the Hiroshima bombing.

A super-sized promotional trick that is now a D.C. landmark.

A haunting tribute to pioneering photographer Clover Adams.

The privately owned cemetery that holds room for Washington's finest when they step down from life.

Art deco landmark on the outskirts of Washington, D.C.

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

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

This leafy estate is worth $18 million and is so grand it has two mailing addresses.

An obscure federal monument honors the French diplomat who served as Ambassador to the U.S. during WWI.

There’s a special club house at the top for the bell ringers.

There just so happens to be a court even higher than the U.S Supreme Court: a basketball court in the building itself.

Housing the National Women's Party since 1929, this historic house is now a monument to the fight for gender equality.

One critic described it as "middle Mussolini, early Ramses, and late Neiman-Marcus." Another called it an architectural "natural disaster."