This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.

This former Roman Catholic Church still contains the embalmed hearts and organs of 22 popes.

Fountain where visitors can earn a license to be mad.

A large grotto built in the 16th century amidst Florence's famous Boboli gardens.

This bronze boar's snout has been rubbed to a golden sheen by visitors seeking good fortune.

The famous sculptor left his mark on this Italian wall in an internationally protected example of street art.

Secret refuge and museum of the Duke of Florence.

The capital of the Cayman Islands is a center of offshore banking, but gets battered by blistering hurricanes.

A lovers' beach, tucked below the surface of the island, provides a safe haven for romance.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

Every equinox this Maya pyramid puts on a spooky ancient light show.

Rusty red sands line the shores of this Canadian Province.

The semi-reclaimed ruins of this canal were once part of an ambitious plan to reroute the mighty potomac.

This phone booth-sized municipal building has been a piece of police property for more than half a century.

A 56-foot tall statue of the god of fire looks out over Birmingham, Alabama.

You have to love a museum with a truly dedicated focus. A focus on Superman, for example.

A bizarre roadside attraction and the first instance of miniature golf in the world.

The world's longest known cave system.

Home of an evil witch famous within southern folklore.

This replica of the Greek structure is in the heart of Nashville.

Labor provided by Great Depression-era programs restored these 25,000 acres in Tennessee.

Mile-long cave system near Great Smoky Mountains.

A recreation of the doomed ocean liner in the middle of the Smoky Mountains.

Enormous lake at the bottom of a unique cave system.