The U.S. Fish Commission’s effort to mass produce carp.

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

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

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

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

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

This unique museum cafeteria showcases the history and regional diversity of African American cuisine.

Seemingly unremarkable items like empty sushi trays, chef hats, and freshness stickers are being preserved so future generations can look back on this beloved cultural import.

A heroic pigeon that, through a barrage of gunfire, delivered a message that saved over 100 lives in World War I.

This taxidermy horse was a Civil War hero.

The most decorated dog of World War I is preserved in the Smithsonian.

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

The 28,000-year-old specimen is remarkably intact.

This stunning blue and gold room changed cities twice before becoming part of the Smithsonian.

The remains of Martha, the last known passenger pigeon, serve as a tool to educate about conservation.

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

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

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

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

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

A museum cafe showcases Native American dishes and indigenous ingredients from across the Western Hemisphere.

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

Home to items never before seen by the public.

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