The crypt of the imposing Stephensdom holds royal intestines and thousands of skeletons.

Jesus' footprints and the first catacombs in the world.

An ossuary built in 1210 to collect bones from the Ospedale Maggiore of Milan.

Artfully arranged bones of 5,800 Austrians.

The remains of 40,000 humans, meticulously stacked in a tiny churchyard shed.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

A church of bones, decorated with 40,000 human skeletons.

The bones of some 7,000 soldiers killed in the historic Battle of Solferino are stored here.

The walls and ceiling of this Polish church are decorated with thousands of skulls, with another 21,000 skeletons just below.

An 18.9-meter tower that pays tribute to the Pennsylvania-German pioneers who settled the Waterloo Region between 1800 and 1803.

Known as the "Kissing Bridge" for its privacy, it also happens to be the last covered bridge in Ontario.

It took over 100 years to decode this enigmatic epitaph for two buried brides.

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

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

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

The privately owned cemetery that holds room for Washington's finest when they step down from life.

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

For 60 years, the academy had no permanent location until members voted Washington D.C. as its forever home.

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

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

Long-abandoned trolley tunnels just a mile away from the White House are turning into an art space.

This elegant structure at the heart of a Finger Lakes town was originally a drinking fountain.

There is no trying to fall in love with this Star Wars fountain, you just do or do not.

The remnants of two World's Fairs are here, complete with a 12-story globe, a mini-Manhattan, and a UFO-shaped pavilion.