Live data is transmitted from the Atlantic coast to instantly recreate the ocean waves in this fountain at the NOAA headquarters.

Giant acorn-shaped 19th century gazebo from which suburban Washingtonians gazed upon the original "silver" spring.

A girls' boarding school inspired by the Chicago World's Fair, once abandoned, now restored to strange and scenic glory.

100 years later, they're still down there.

An obscure public service from the U.S. government that redeems burnt, moldy, and soiled old greenbacks.

Perhaps the most scandalous statue of America's first president.

A three-story tower of books about Abraham Lincoln is one of the more unusual monuments to the president.

The winding route passes through an enclosed alleyway, two tunnels, and leads to the White House basement.

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

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