Bizarre Cavern.

A sprawling maze of used books piled from floor to ceiling.

Built around 1723, this is the oldest surviving home in the U.S.'s oldest colonial city.

A tribute to Ponce de Leon's supposed quest for eternal youth.

One of the oldest, tallest, and most haunted lighthouses in America.

This massive cave is a sight to behold.

This papier-mâché diorama celebrates an unusual landmark: the brightly-colored runoff from a local sock factory.

An institution that preserves the history of institutionalization.

An emporium for the weird, creepy, rare, and just plain gross.

Instead of fruit, the branches of this tree are brimming with hopes and dreams.

Entering this curiosity shop is like stepping into a mad scientist's lab.

No two pieces are exactly the same at Portland's hippo-themed hardware store.

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

The largest of London's subterranean rivers and once a mad, bad center of London life.

This one has sailed five times as far as Sir Francis Drake's famous ship.

Tucked away in the Tower of London is the weapon once used to execute high-profile prisoners.

Richard III supposedly disposed of his nephews' bodies here in an effort to seal his claim to the throne.

Graffiti from the 16th and 17th centuries cover the walls of this part of the Tower of London.

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

The London pub overlooks where the Mayflower was moored before setting sail for the New World.

The handiwork of a underdog clockmaker who solved an impossible problem for an Empire, and forever revolutionized seafaring.

Thanks to modern navigational tools we now know that the true prime meridian runs through a park next door.

A charming monument to a very special dog.