A promising candidate for the lost rock laid by George Washington was unearthed, but the hunt is still on.

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

This forgotten boat elevator was an engineering marvel in its heyday.

An echo chamber with a waterfall wrapped around its base at the Embassy of Canada in Washington, D.C.

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

A hidden gem on the lawn of the U.S. Capitol Building designed by landscape architect Frederick Law Olmsted.

After his presidency, George Washington planned to live only a few blocks from the Capitol building.

Atop this media building, two hives containing more than 30,000 bees keep the surrounding area vibrant.

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

This historic building is now home to the Public Access Corporation for the District of Columbia.

Home to two notable early-20th-century Black educators, Lucy Slowe and Mary Burrill.

One of the first Second Empire-style buildings constructed in North America.

This grisly headstone doesn’t seem to be resting in peace.

The towering figures were created from the cemetery's fallen old-growth trees.

The former home of the woman who successfully fought to integrate restaurants in Washington, D.C.

‘Bush the old fire dog died of poison July 5th, 1869. RIP.’

The early data processor factory founded in Washington for the 1890 U.S. Census went on to become IBM.

A historic ruin just 20 feet away from a busy highway onramp.

A small token of gratitude from freezing cold journalists who were given a warm haven while covering JFK's inauguration.

An 18th-century townhouse that once hosted guests of the president.

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

This supermarket offers shoppers a window into the past alongside their groceries.

Experience what life was like in Ireland during the Viking and medieval ages.

At Washington's Dulles Airport is a satellite museum (no pun intended) with three quarters of a million square feet of aircraft history.