Oldest existing church in New York and the inspiration for Washington Irving's "The Legend of Sleepy Hollow."

Wedding chapel's mysterious spiral staircase said to be miraculously constructed.

A former waterfront market is now in the center of town due to some interesting Boston engineering.

Twisted buildings adorn the banks of the Rhine river.

Artfully arranged bones of 5,800 Austrians.

A multi-storied adobe complex has been inhabited for more than a thousand years.

66,000 pieces of art, donated by one of the world's richest men.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

Civil War Fort on an island in the Boston Harbor.

The site of Paul Revere's historic two lantern warning.

This landmark cemetery in Boston was created more than 300 years ago.

Statue commemorating the use of ether in anesthesia.

Each August, one of the largest religious (and food) celebrations in the country is held in Boston.

The oldest Italian café in Boston, this spot also serves as a veritable museum of vintage coffee ephemera.

A marvel of Byzantine engineering under the streets of Istanbul.

What was once a true peninsula has now been filled in, causing the water to recede and leaving many streetside "waterfronts" and landlocked "islands."

The American Revolution was galvanized into serious action due to the tragic clash with British soldiers that occurred at this location.

An Ethiopian "Jerusalem" featuring a church hewn out of a single rock.

An Aztec temple, the largest man-made pyramid in the world, sits buried in earth with a Spanish church set on top.

The only castle in North America to ever house European sovereigns.

A small but immensely extravagant palace built by the "Night King."

The fairy tale castle of the “fairy-tale king,” this was also the inspiration for Disney’s “Sleeping Beauty.”

This former insane asylum now holds a pathological anatomy museum.

The topiary maze at the Habsburg hunting lodge.