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

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

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

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

An extensive, if one-sided, history of U.S. law enforcement's war on drugs.

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

Soldiers were buried next to Lee's house in the center of Arlington Cemetery to dissuade the general from reclaiming his property after the war.

A nostalgic bibliographic gem.

Giftshop catering to cryptozoologists and anyone with a sense of humor.

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

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

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

The country's oldest continually-operated mini golf course lies hidden in plain sight, eclipsed by one of D.C.'s most popular tourist attractions.

A wondrous old library overlooking the nation's capital.

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

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

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

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

"Congress may voluntarily remain in session throughout the summer, in order that our Congressmen may be protected from the intolerable discomforts and dangers of the ordinary outdoor weather!”

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

A traveling postal dog covered 48 states and more than 140,000 miles, and he lives on as taxidermy, patched up with a rabbit's foot and a pig's ear.

Helen Keller once broke ground on this historic center for the study of technologies to benefit the hearing impaired.

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

Need a hardcopy of the 50-title Code of Federal Regulations? This is the place.