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

Government testing at the asylum briefly explored using marijuana as a "truth serum" on Nazi prisoners of war.

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

Politicians, bureaucrats, and military officers gathered in this field near the Capitol to settle their disputes with blood.

The United States Capitol's former columns still stand.

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

A striking memorial to the 21 lives lost in an explosion at the Washington Arsenal

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

One of the largest artillery pieces in the world sits in a Washington D.C. parking lot.

Part of a WWII submarine is lurking outside the Washington Navy Yard parking lot.

An extensive, if one-sided, history of U.S. law enforcement's war on drugs.

Depending on who you ask, this controversial treehouse is either a charmingly creative child's playhouse or an illegal encroachment on public land.

Soldiers were buried next to Lee's house in the center of Arlington Cemetery to dissuade the general from reclaiming his property after the war.

A replica of the famous memorial statue at the Normandy American Cemetery hides in an office building in downtown D.C.

One of the three perfect vellum copies of this historic book known to exist is on display in a specially-designed case.

This groundbreaking 16th-century map is known as "America's birth certificate."

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

The only National Monument ever to go missing for nearly 50 years then resurface in a dump.

This statue of the "father of television" stands prominently in the United States Capitol.

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

"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!”

Corn-inthian columns with a uniquely American take on neoclassical architecture.

Railroad officials in the early 1900s sought to spare travelers the sight of Roman soldiers’ private parts.

A historic arena where the Beatles played their first concert in the U.S.