The highest point in Washington state is a volcano covered in glaciers.

A real (but thankfully not live) missile stands tall as a monument to the United States military in the small town of Cordele.

North Central Florida's largest flea market and a weekend roadtripper's dream.

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

The scuba diving training facility was named for the steam that rises from the cave's chimney.

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

An octet of classic chrome trailers speared into the ground act as a tribute to the silver bullets of the open road.

Possibly the most beautiful carillon in the world, set atop Iron Mountain in Florida.

The unique collection includes bronze cast handprints of some of America's most famous astronauts.

A building so large that it has its own weather.

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

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

Museum celebrating the history of computers, especially their role in codebreaking.

Home to Alan Turing, the cracking of the Enigma code, and Captain Ridley's shooting party.

Home to items never before seen by the public.

This candy-colored storybook village originated as a 19th-century Methodist campground.

This small-town pizzeria won the Hollywood lottery.

Experience the hysteria of a 17th century witch hunt through goofy reenactments and wax dummies that should probably be burned at the stake.

More than 2,000 species of tropical plants call this nature preserve and sanctuary home.

This unusual lava tube spouts seawater during high surf.

Watch the newest land on the planet form before your eyes.

Earth's tallest volcano is sacred to Native Hawaiians, and home to a dozen world-class observatories.

This black shoreline is made up of exploded lava particles.

An opal mining town in the middle of Australia where people live, worship, and shop underground.