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

This strange geological landscape erupts with sudden bursts of water.

The glacier tucked within a New Zealand rainforest.

This electric green sulphur lake in New Zealand looks like a cartoonish radioactive dump site.

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.

A castle hand-built by a Spanish dreamer in the Australian tropical jungle.

One of Australia's famed "Big Things," this giant fruit was once stolen as part of a publicity stunt.

A small, but award-winning beach known for its literally spotless reputation.

Come for the flowers, stay for the bats!

This trio of Australian rock spires may have inspired aboriginal legend or just modern tourism.

WWI hospital ship lost in a cyclone turns up on the coast of Fraser Island, where she remains rusted and forgotten.

The only pollutant in the clear blue water is sunscreen.

One of the first big sculptures anywhere in Australia.

A giant Australian fruit and tropical farm.

Brisbane's manmade urban beach has enough water to fill five Olympic-sized swimming pools.

Carvings in Turkey's Marble Road may have directed ancient Romans to a hidden brothel.

The ancient latrines of the Greeks, in all their public glory.

A Turkish ghost town abandoned in a population exchange with Greece.

These tombs were built into the side of a mountain so that ancient angels could reach the dead.

Roman ruins top white travertine terraces formed by ancient hot springs.

The only way to see Pittsburgh is from the top of this lookout point, just like the ancient members of the native peoples did.

The United States’s oldest funicular railway glides up and down a steep Pittsburgh street.

One of the steepest streets in the United States makes an intriguing challenge for cyclists.