One of the world's largest Tesla coils.

New Zealand's west coast is one of the best places in the world to view these large seabirds.

This sublime architectural marvel is a rare example of an expressionist church.

Unable to build support structures on glaciers, the engineers for this tramway were forced to design a unique system.

An icy lake tucked among jaw-dropping alpine panoramas.

Every summer, an open-air swimming pool appears at the base of a Finnish city's beloved winter attraction.

An ancient capital city that dates back 3,000 years old and harbors many surprises.

Nightmarish example of the unintended consequences of weapons testing.

Legend has this precariously placed rock was placed by giants. Science has another explanation.

The water swaps direction twice a day, whipping into a frenzy of whirlpools and rapids.

These Finnish rapids have been attracting tourists for over a hundred years and are now released with the push of a button.

Hidden in a Scotland museum is a copse of extinct tree stumps.

This narrow canyon has been carved by the river over thousands of years into spectacular and curious forms.

A tiny microvalley etched into the side of Knocknarea Mountain hides another world.

Every equinox this Maya pyramid puts on a spooky ancient light show.

Every spring, locals see the shadowy figures of a ghost army of slain Greek soldiers descend upon this ruined fort.

A flooded Mexican cave that hides a river beneath the water.

These azure waters were thought to lead to the Mayan Underworld.

This blowhole is supposedly caused by a trapped monster.

Ruins and statues dot the landscape of this tiny island rich with royal history.

This natural sea cave hides a small wonderland of natural turquoise beauty.

If you can look past the nearby sewer pipes, this urban sinkhole grotto is a mini-paradise.

This industrial area was the dumping ground for massive amounts of trash, some of which washes up as tiny bits of sea glass.

A once-glowing grotto at the bottom of Waikapalae Wet Cave.