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

The largest stone circle in the world has ended up bringing up more questions than it has answered.

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

A still functioning vaudeville carousel that has operated for over a century boasts a colorful menagerie and past.

A building so large that it has its own weather.

"We Seceded Where Others Failed."

The highway's southernmost spot is a beloved local attraction.

The former home of the Nobel Prize-winning American writer is now home to dozens of six-toed cats.

The famous winding walk at Chartres is surrounded in mystery and myth.

One part local history, 99 parts gruesome haunted house.

The only visible reminders of an elaborate engineering project that kept the tower from reaching the tipping point.

A copy of the famous statue can be found in this Florence piazza, along with one of the most breathtaking views of the city below.

The mummified relic of St. Antoninus.

The oldest operating pharmacy in the world features 800-year-old recipes.

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.

Drink wine handed out through a window as part of an age-old tradition.

2300-year-old Roman road connecting the empire.

The ruins of the largest gladiatorial school in Rome are largely hidden under modern streets.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

60 feet of towering steel balances gracefully.

Dentist's hated concrete colossi are now beloved icons of the community.

His discovery kicked off the Gold Rush. One of the hands on this commemorative statue points to the spot where he found the precious metal.

A few iconic structures are all that remain of America’s first outdoor shopping mall.

This centerpiece of the Hollywood & Highland shopping center is a recreation of a long-lost movie set.