While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

Daredevil repair workers can worm their way out the access hatch, loop ropes over the apex and rappel down the monument.

The monument's pointy aluminum tip has been melted down by repeated lightning strikes.

An unassuming, powerful monument north of the U.S. Capitol bears witness to the resilience of Japanese Americans during a time of grave injustice.

Home to a vast and influential collection of Shakespeareana.

The institution is sitting on a goldmine of 21,000 paints, varnishes, pigments, and primers preserved for posterity.

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

A hoard of sky catalogs, astrophysical journals, even the works of Galileo and Copernicus.

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

The most accurate timepiece in the world.

D.C.'s first central library was born out of a chance encounter with the philanthropist whose name it bears.

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

A nostalgic bibliographic gem.

A historic estate packed with George Washington's heirlooms, and its own nuclear bunker.

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

A monument in Washington D.C. marks the spot from which all other roads were supposed to stem.

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

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

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

Whether you're up or down, the Elevator Museum is worth a stop.

A Natural History and Science Emporium.

A Bed-Stuy gymnasium that hosts expansive raves, performances, dance parties, and more.

A Brooklyn exhibit all about Nancy Kerrigan and Tonya Harding in 1994.

Walk over a 150 year old manhole.