Medieval museum built over Roman baths that features famous tapestries of a lady and a unicorn.

This 1830s store is believed to be the site of Harriet Tubman's first stand.

These remote Florida islands have a history of sea turtles and sunken treasures, and one of the world's largest coastal brick fortresses.

The last remnants of a massive medieval wall that once encompassed the city of Berlin.

A museum of anything and everything Stooge.

The oldest residential street in Europe also features an optical illusion.

Constructed during the 7th century this is one of the oldest largely intact Christian churches in England.

The medieval legend behind this holy well was one of the inspirations behind "Alice's Adventures in Wonderland."

A surprising, but overlooked example of geology in the middle of the nation’s capital.

An overlooked tribute to one of the most important peace deals in American history.

After his presidency, George Washington planned to live only a few blocks from the Capitol building.

Sit where JFK proposed to Jackie or where Nixon dined on meatloaf at this storied pub.

This grisly headstone doesn’t seem to be resting in peace.

One of the most influential presidents in U.S. history wanted only this plain, elegant monument as his lasting memorial.

A tiny monument to the unsuccessful attempt by Thomas Jefferson to place the prime meridian in Washington.

This grand gothic brewery has been pumping out suds for over a hundred years.

The remains of the man who founded Pennsylvania lie in an unassuming grave in the English countryside.

An engineering error ensured this cavernous 350-foot-long subterranean thoroughfare was never used as intended.

A labyrinthine underworld of tunnels and caverns hides beneath the city.

A mapping error in the 19th century made loggers think this section of the forest was underwater.

This tiny river island switches sovereignty every six months as part of a rare, centuries-old agreement.

A wonderfully eclectic Victorian aquarium lies in the basement of the Horniman Museum.

This religious museum resides in a church crypt next to the founder's house.

This innovative steam machine was no doubt the most famous of the pioneer locomotives.