The ruins of an ancient Mayan city, beautifully preserved and only accessible by boat.

An elaborate Mayan city shrouded in alien conspiracy revealed the tomb of Pacal the Great.

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.

St. Augustine's record-setting narrow street was designed to protect against pirates.

The museum chronicling a treasure hunter's dream, fulfilled.

An idyllic swimming pool tells the tale of Hemingway's trouble with women.

"We Seceded Where Others Failed."

This abandoned NASA launch site is now a memorial to a trio of astronauts who were killed there.

One-time winter retreats of prolific inventor Thomas Edison and his friend Henry Ford.

An 18th-century Spanish watchtower made entirely of seashell and concrete.

A monument celebrating the idea of reaching inaccessible places.

A luxurious 1880s hotel with its fair share of Tiffany stained glass, Edison electricity, and of course, ghosts.

One of many gator theme parks, abandoned in the sugar fields of South Florida.

Island ghost town detailing Flagler's folly in building the Overseas Railroad.

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

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

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

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

A fitting attraction for the corn capital of the world.

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

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

This posh mansion began as a family's estate and ended as the site of a murder ripped from the pages of a pulp novel.

These curious caverns have been home to mushrooms, gangsters, and disco.