Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

Come for the pizza, stay for a performance on the world's largest theater pipe organ.

Renaissance hospital featuring a rotating door into which unwanted babies were dropped.

The mummified relic of St. Antoninus.

The doodles of a genius line the walls of a secret room under the Medici Chapel, where they were hidden for nearly 500 years.

A church of bones, decorated with 40,000 human skeletons.

Mummified monks and the accidentally interred, in a 17th-century crypt.

This bustling Italian plaza is built on the ruins of an ancient Roman amphitheater.

Fortified medieval tower house with lovely roof garden.

The naturally mummified body of a peasant girl saint.

Known as the "Hobbit Houses," these storybook homes look like they're straight out of the Shire.

The shortest river in America flows for just 201 feet.

Thanks to a loophole in property ownership, this alleyway has become a cacophonous street gallery.

This prehistoric sinkhole lured exclusively male mammoths to their death, much to the delight of science.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

An impressive collection of farm equipment and other artifacts from life on the prairie.

One of America's first dinosaur parks gives a window into Depression-era paleontology.

Every president in history is immortalized in bronze in downtown Rapid City.

One of America’s oldest and spookiest hotels, thanks to the residency of ghosts, dead presidents, and Alfred Hitchcock.

A place where the laws of nature seem to have gone completely berserk... but of course haven't.

This replica stave church looks like a piece of Norway was simply plopped down in South Dakota.

South Dakota's oldest operating brewery is housed inside a historic firehouse.

A six-ton, 12-foot-tall concrete prairie dog is touted as the largest in the world.

The granddaddy of all tourist traps, built on ice water, jackalopes, and a giant dinosaur.