The remains of the left arm of the levitating philosopher-saint are kept in a 13th-century Neapolitan basilica.

Eighteenth century house of the mysterious "Father of Raleigh."

At Washington's Dulles Airport is a satellite museum (no pun intended) with three quarters of a million square feet of aircraft history.

In this case, 'zero' marks the spot where the iconic Old Spanish Trail ends.

Location of a reliquary containing bone fragments of 18 saints.

Church featuring "high Victorian gothic" architecture.

The four tall pillars once marked the entrance of the historic Seattle church that fought for women's suffrage and civil rights.

The above-ground crypts at this Catholic cemetery face north-south instead of the usual east-west.

This colonial tavern played host to George Washington, Thomas Jefferson, and other famous early Americans.

Remote ruins of a 2,400-year-old Iberian settlement.

Largest Roman Catholic church in North America.

The final resting place of two (or three) presidents, one vampire, and 18,000 Confederate soldiers.

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

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

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

The rogue roots are gradually consuming some of the historic marble grave markers.

On the Fourth of July this area will transform into a Pompeii-like storm of falling embers and ash.

The controversial urban planner who designed Washington, D.C., was buried in Maryland, and can presently be found in Virginia.

The Pentagon sits on a former island that was in Virginia at low tide and D.C. at high tide.

The Pentagon is so large that it was planned like a city, complete with internal highway infrastructure.

The gorgeous entrances into the city's underbelly look more like grand halls than subway stops.

A portal into the bricked up canal that runs through the heart of Washington D.C.

A historic ruin just 20 feet away from a busy highway onramp.

This robust fence in front of a historic Georgetown home is likely made from hundreds of recycled Revolutionary War firearms.