A sacred site for Native Americans surveyed by George Washington and owned by both King George III and Thomas Jefferson.

These powerful, if squat, Canadian waterfalls flow in different directions depending on the time of day.

Go inside to really appreciate this 500-year-old technological masterpiece.

This Roman statue is missing a limb from when the Venetians stole it from Constantinople during the Crusades.

Two stone columns flank the grand Venice square, but there were supposed to be three.

A slightly creepy gallery of plaster cast models in the same museum as Michelangelo's David.

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.

A dismembered holy head stares out from her beautiful reliquary at the St. Dominic Basilica.

What appears to be an ancient Roman temple is actually a Catholic church.

An ancient Roman temple first dedicated to an emperor's wife is now a church.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

The world's largest fully steerable radio telescope.

Take a steam-powered ride straight out of the past on this Appalachian rail line.

These tourist trap caverns are said to be the former home of a legendary Pennsylvania Hermit.

A local prank turned town icon.

The world's tallest doric column is this Ohio monument to a naval victory in the War of 1812.

These sub-farmland caves are home to a majestic stalactite known as the "Crystal King."

A throwback train ride transports passengers through one of the lesser-known national parks in the country.

The enormous 250-room Vanderbilt mansion conceals hidden doors and secret passageways.

Classy up your Big Mac with bow-tied servers and chandeliers at the world's fanciest McDonald's.

The highest point in Tennessee, Clingmans Dome bears witness to the ravages of one type of insect.

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

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