The walls of America's oldest masonry fort famously "swallowed" cannonballs.

The ruins of a once-thriving sugarcane plantation that was burned in the Second Seminole War.

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

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

Arrr! The most authentic collection of pirate artifacts in the world... matey.

This Florida sinkhole hides a rainforest-like micro-environment in its depths.

Welcome to old Florida, where a 1940s mermaid show is still enchanting visitors.

Minnesota's highest point is a scenic vista marked by a plaque and armies of mosquitoes.

Equal parts record-breaking temple to consumerism and bizarre fun park, it's more than you think it is...

During the solar phenomenon "Lahaina Noon" this bendy, curvy sculpture forms a perfectly circular shadow on the ground.

The only royal palace on U.S. soil has been a territorial capitol, a military headquarters, and a prison for a queen.

The air force base preserves its scars from the Japanese attack on Pearl Harbor.

This legendary urban waterfall creates a dazzling display of rainbows.

Climbing this abandoned railway leads to breathtaking vistas of O‘ahu.

The grandiose interior of this bar speaks to its past as home to famous jewelers and railway offices.

To truly appreciate Detroit's landmark skyscraper, you have to step inside.

This erect, phallic geological spire wasn't always named so domestically.

A collection of 20th-century automata, penny arcade games, and musical contraptions.

One of the best absinthe distilleries in the United States.

Playable, historic pinball machines fill this Alameda museum.

The world's largest collection of fine-scale miniatures and one the nation's largest collections of antique toys.

Ice cream stand, snack bar, and time capsule of milk conveyance.

Macabre headstones carved with winged skulls, dancing skeletons, and pithy reminders of impending death.

This nearly 200-year-old restaurant's history includes an exiled French prince, JFK, and a very hungry Daniel Webster.