Largest tulip festival in America, includes fireworks, a parade, and a carnival.

Through the decades, Black music stars have performed at this historic hub for music and the arts.

A gorgeous mural outside a beloved D.C. restaurant pays homage to famous Black Americans.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

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

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

A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.

Legend has it that President Grant’s frequent drinking in the lobby gave rise to the term “lobbyist.”

The oldest building in the District of Columbia was preserved because of a mistaken connection to George Washington.

Members of Congress have traveled between the buildings on Capitol Hill for a century hidden from tourists, press, and storm clouds.

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

The national park was once a plantation estate.

It was once the base for a series of domestic terror attacks.

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

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

The Byzantine, pre-Columbian, and medieval art at this stately mansion are some of the most under-appreciated collections in D.C.

The beloved statue at the National Academy of Sciences is oh so inviting to sit on.

The walls of the iconic dome are hollow and have a secret stairway.

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

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

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

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

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

This elaborate towering structure was once famed for its revolutionary height.