Those belting out show tunes might not realize this piano bar marks the site where Thomas Paine died in 1809.

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

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

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.

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

When it comes to handsignals (and colonialism) rock always beats scissors.

A painfully obvious spy house sits right across the street from the Russian Embassy.

This robust fence in front of a historic Georgetown home is likely made from hundreds of recycled Revolutionary War firearms.

The unique traffic pattern named for an influential urban planner is also known as the Pedestrian Scramble.

Housing the National Women's Party since 1929, this historic house is now a monument to the fight for gender equality.

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

The spot in the Mile-High City that's exactly 5,280 feet above sea level (at least for now).

The Denver airport is guarded by a 32-foot-tall sculpture of a demonic horse.

One of the greatest heroes of the Titanic tragedy came from humble beginnings to this beautiful home.

Before Nixon, "watergate" meant canals.

The most accurate timepiece in the world.

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

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

A super-sized promotional trick that is now a D.C. landmark.

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

A 1,100-ton train fell through the floor in 1953. Workers got it patched up in just 72 hours.

A muscular Art Deco monument represents the struggle between regulators and unbridled markets.

This seemingly out-of-place gas station by the Watergate hotel was once described as the most expensive gas station in the world.

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