A celebrity from the late Cretaceous period.

The only Civil War battle in Washington D.C. took place near this highest natural point in the city.

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

The iconic D.C. restaurant where the Cuban Missile Crisis was negotiated, now a Walgreens.

A portal into the bricked up canal that runs through the heart of Washington D.C.

On the Fourth of July this area will transform into a Pompeii-like storm of falling embers and ash.

A small Richmond island dotted with the remnants of hundreds of years of history.

Heron, whitewater rapids, and urban industrialism all add to the beauty of this concrete nature walk.

Formerly the most gerrymandered district in the U.S., it twisted and turned along racial borders.

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

This grand gothic brewery has been pumping out suds for over a hundred years.

A small triangle of DC grass is the final resting place of one of Sonny and Cher's songs.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

This mysterious structure by the Washington Monument is a flood barrier designed to protect the White House against rising waters.

A tiny monument to the unsuccessful attempt by Thomas Jefferson to place the prime meridian in Washington.

There's a 12-foot-tall replica of the Washington Monument hidden under a manhole nearby.

The hidden offices underneath Memorial Bridge have been locked up since 1976.

Parking garage where Bob Woodward met Watergate source "Deep Throat."

A derelict bit of transportation infrastructure hidden in the woods.

The little-known, 300-year history of the area includes former lives as a bustling tobacco port, parking lot, and industrial dump.

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

Before Metro, Washington had a robust streetcar network—and you see the remains of this infrastructure if you know where to look.

Look closely and you’ll notice that the color changes a third of the way up the tower.

This lonely waterfront memorial to the men of the Titanic was erected by the "Women of America."