The only working large-scale tea plantation in the United States.

One of the oldest living oak trees in the Southeast.

I-95's Tijuana-style celebration of kitsch at the Carolina border.

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

Decades before the scandal, this staircase on the river was a literal "water gate."

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

Franciscan monks created a facsimile of the Holy Land for North Americans who couldn’t afford the trip overseas.

Largest Roman Catholic church in North America.

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

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

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

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

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

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.

Home to items never before seen by the public.

The bank that helped fund the Mexican-American War and the purchase of Alaska met its downfall after helping Augusto Pinochet launder money.

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

Legend has it that President Grant’s frequent drinking in the lobby gave rise to the term “lobbyist.”

Disks are rolled out onto the south lawn to absorb the impact of Marine One's wheels like giant coffee coasters.

The "lovely red Vega" of the legendary record-settling pilot.

Washington's iconic carousel has a nice piece of Civil Rights history.

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

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.

Conjoined twins Daisy and Violet Hilton were stars of the vaudeville circuit.