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

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

The national park was once a plantation estate.

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

The bad-ass ride of a soul legend, housed in one of the world's few soul museums.

This Memphis recording studio launched the careers of Jerry Lee Lewis, Johnny Cash, and Elvis Presley.

The hotel where Martin Luther King Jr. was shot is now a museum dedicated to his work.

A completely round house designed for the Atomic Age.

This small church was constructed over the ruins of three temples dating to the Roman Republic.

This is the oldest Roman-made bridge in the city still existing in its original state.

A detailed pachyderm supports Rome's smallest Egyptian obelisk.

Breathtaking and huge 430 year old maps of Italy.

If you want to talk to the Pope you will have to stare down this surreal vision of Jesus rising from a nuclear hell.

These spartan apartments are provided to clergymen visiting Vatican City.

Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

This equestrian statue of Constantine the Great has been the subject of criticism for centuries.

The Vatican's secret porn-festooned bathroom was painted in erotic murals by one of the greatest artists of the Renaissance.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

An 18th century fountain and two columns are all that remains of Rome's forgotten river harbor.

An ancient Egyptian obelisk is now used to commemorate fallen Italian soldiers.

Installed in an act of one-upsmanship, the annual sundial in this church is also a symbolic victory for the Gregorian calendar.

Ancient ruins hidden underneath a modern luxury hotel.