It was once the base for a series of domestic terror attacks.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

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

This sandwich shop has a century-old elevator behind a sheet of plexiglass.

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

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

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

There’s a hidden military meme engraved on the World War II Memorial.

The beloved statue at the National Academy of Sciences is oh so inviting to sit on.

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

Fittingly, America's museum of architecture is itself a magnificently designed old building.

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

A cemetery housing wild west legends in South Dakota.

More than 150 working bells from churches and one-room-schoolhouses across the Great Plains are assembled in one man's yard.

The first "Hut" was actually a small brick building.

A museum where visitors can learn about greyhounds and (more importantly) pet them.

A Victorian mansion, painstakingly reproduced to appear just as the the Munster's family home did on TV.

World's smallest skyscraper, the product of a remarkable con.

The 40-foot-tall votive candle is the largest of its kind.

These boots are made for selfies.

A 24-hour vending machine restocked daily with homemade full-sized pecan pies.

The pit stop from "The Texas Chainsaw Massacre" now serves beef and pork barbecue, not people.

The world's largest squirrel statue clutches a pecan bigger than your head.

Housed in a century-old building, this museum's dedicated not just to soft drinks, but to the free enterprise system.