The house where John Wilkes Booth conspired with his co-conspirators.

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

The first purpose-built art gallery in the United States is once again open as a center of craft arts.

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

Largest Roman Catholic church in North America.

When it opened during the final years of the embargo, all the drinks and cigars were free.

A rotating cast of guys and dolls in front of a Washington, D.C. building.

This stunning blue and gold room changed cities twice before becoming part of the Smithsonian.

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

A cavernous three-story, 43,800-square-foot basement that was forgotten about for 60 years.

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

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

The United States Capitol's former columns still stand.

Long-abandoned trolley tunnels just a mile away from the White House are turning into an art space.

The site of the climactic scene from the classic horror film is now a historic landmark.

A whopping 14,000 copper coins cover this miniature fighter jet.

Oldest unrestored plantation house in America that is open to the public.

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.

At 207 feet, one of the world's longest continuous escalators.

Charleston's historic city jail once held everyone from pirates to Civil War POWs.

A sacred site for Native Americans surveyed by George Washington and owned by both King George III and Thomas Jefferson.

"X" marks the spot of an echo chamber in the middle of a plaza.

One of Savannah's oldest and most haunted cemeteries, featuring graves desecrated by Sherman's Union Army.

This haunting tombstone comes complete with a heartbreaking story of love and loss.