The busy transport hub is home to the tallest airport slide in the world.

The highest pedestrian bridge in Singapore looks like a series of undulating waves rising between two public parks.

The largest pool at its elevation sits on top of one of the most expensive resorts in the world.

Singapore's landscaping project is home to 18 incredible Supertrees.

A humid oasis combines recreation with exploration in a unique underwater cavern.

Discover diverse aquatic life and befriend resident turtles at this private diving grotto in north Florida.

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

Where manatees are the snowbird vacationers in these balmy Florida springs.

The behemoth beasts engaged in an epic battle is the second-tallest statue in the contiguous United States.

A steamer run aground near Bimini lives a second life as a playground for scuba divers.

An underwater road considered a possible Atlantis location.

Send a postcard while vacationing with Satan.

The capital of the Cayman Islands is a center of offshore banking, but gets battered by blistering hurricanes.

The ruins of an important pilgrimage destination for worshippers of a Maya fertility goddess.

Few of the many visitors to this resort town know of its hidden Maya ruins.

An ancient system of freshwater caves filled with animal bones, including that of species long-extinct.

A natural formation that resembles a camel resting in the New Mexico desert.

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

The land is full of geologic eye candy, such as otherworldly spires, mushroom-shaped hoodoos, and prehistoric fossils.

Seemingly grown on some other world, these New Mexico rock formations look like a disused science fiction set.

Legends surround this jagged rock formation in the New Mexico desert.

On the edge of grassland in northeastern Colorado, these rock formations are some of the few remnants of a high plain that has eroded away over millions of years.

This remote Colorado canyon is home to the second-largest collection of natural arches in the world.