D.C. once had its own tiny rival to the New York Stock Exchange.

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

There’s a special club house at the top for the bell ringers.

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

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

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

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

There just so happens to be a court even higher than the U.S Supreme Court: a basketball court in the building itself.

Where the U.S. government kept its actual treasure, before Fort Knox.

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

This imposing Masonic temple a mile from the White House was the first public library in Washington, D.C.

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

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

This leafy estate is worth $18 million and is so grand it has two mailing addresses.

Long-abandoned trolley tunnels just a mile away from the White House are turning into an art space.

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

Bar full of oddities, specimens, artifacts and homages to the great dime museums of the past.

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

This stoic, if derpy, giant stands as a monument to Oregon's statehood and the novelty culture of yesteryear.

Portlandia is the second-largest copper repoussé statue in the United States.

Delightful disarray of found objects and clutter.

Featuring a casually threatening atmosphere along with dessert and coffee to die for.

The magic's in the hole!

A heavenly experience, right here on Terra Firma.