Government in Washington, D.C.

There's a 12-foot-tall replica of the Washington Monument hidden under a manhole nearby.

Seemingly unremarkable items like empty sushi trays, chef hats, and freshness stickers are being preserved so future generations can look back on this beloved cultural import.

An atomic bomb-proof strongbox protects the U.S. Constitution from terrorists and thieves.

Need a hardcopy of the 50-title Code of Federal Regulations? This is the place.

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

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

This mysterious structure by the Washington Monument is a flood barrier designed to protect the White House against rising waters.

"Congress may voluntarily remain in session throughout the summer, in order that our Congressmen may be protected from the intolerable discomforts and dangers of the ordinary outdoor weather!”

Washington's top-secret Cold War-era doomsday communications tower is located in a small neighborhood park.

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

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

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

A small triangle of DC grass is the final resting place of one of Sonny and Cher's songs.