People escaping slavery may have hidden inside a corpse vault.

Sit where JFK proposed to Jackie or where Nixon dined on meatloaf at this storied pub.

The sci-fi villain is a little-known inhabitant of the U.S. capital's largest cathedral.

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

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

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

This unique historical monument features large concrete spheres designed to resemble fallen stars.

The rogue roots are gradually consuming some of the historic marble grave markers.

A derelict bit of transportation infrastructure hidden in the woods.

Once home to seven different roller coasters, Glen Echo has undergone many transformations since its founding in 1891.

This ruined quarry once produced the distinctive red sandstone used for construction projects in Washington, D.C.

Located at the former Lorton Prison the Lucy Burns Museum tells the story of the 91 year history of the prison including the dark chapter of its involvement in the women's suffrage movement.

An out-of-place Air Force radar dome is all that denotes this park as a former missile launch site.

Exact replica of the ancient monument, but much, much lighter.

This stately mansion, built in 1787 by America's first Secretary of the Navy, is rumored to be one of the most haunted buildings in Washington, DC.

This sandwich shop has a century-old elevator behind a sheet of plexiglass.

The most accurate timepiece in the world.

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

A Spiritualist house of worship where believers communicate with the dead in the spirit world.

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

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

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

A historic neighborhood church is reborn as a psychedelic arts collective.