The hotel where Martin Luther King Jr. was shot is now a museum dedicated to his work.

Send a postcard while vacationing with Satan.

This replica of the Greek structure is in the heart of Nashville.

A New Zealand communications tower stands as the tallest structure in the Southern Hemisphere.

Highly spherical boulders on the shores of New Zealand.

A 90-foot-tall psychedelic "tree" on the side of the highway has baffled passersby for decades.

Inside this striking glass building, visitors can see thousands of dinosaur fossils in the positions that nature deposited them more than 150 million years ago.

Deadly scalding and one of the largest hot springs in the world.

Major tourist destination known for its bubbling mud-pools and hot thermal springs.

This strange geological landscape erupts with sudden bursts of water.

A glacier pocked with ice caves and surrounded by rainforests.

Dolphins, ancient clams and hundreds of waterfalls make this one of the world's top tourist destinations.

Tubing through a cave lit with glowworms is a magical underground experience.

At this Denver landmark, the meals are compulsory, the sopapillas are complimentary, and the insanity is everywhere.

This immigrant bridge once spanned the Thames but is now a fixture of an Arizona city.

This 40-room dwelling tucked within a cliff was built by the basin's prehistoric residents.

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

Giant works of art interspersed throughout meadows and woodlands offer a new discovery at every turn.

An adorably sweet display of sculpted Precious Moments figurines.

Speak to a companion on the other side of the room loud and clear through this architectural anomaly.

Giant granite rocks standing end-to-end like a train of circus elephants.

The show pony of cave systems, Fantastic Caverns manages to live up to its name.

Erosion and time have created a naturally-formed water park.

400 million-year old limestone caverns nestled in the Ozarks served as shelter and a hideout for cultures throughout North American history.