This ruined fort and statue are a testament to the last king of Kaua‘i’s savvy diplomacy skills, which briefly brought Russians to Hawai‘i.

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

This narrow coastline trail through the dense Kauai wilderness is among the most beautiful and dangerous in the world.

Submerged lava formations create incredible waterworks.

A unique set of caves that spits waves back out into the ocean.

A series of waterfalls and pools that flow through the 'Ohe'o Gulch and into the ocean.

This legendary urban waterfall creates a dazzling display of rainbows.

This unusual lava tube spouts seawater during high surf.

Football field-sized microalgae production tanks on the Hawaiian coast create a stunning view from space.

The Yonaguni Monument, a natural formation or the Japanese Atlantis?

Hidden just under the waters around this Turkish island are the ruins of a once great city.

One of the most exquisite Lycian hilltop citadels in Turkey.

A Lycian city of the dead carved into the hillside of Southern Turkey, complete with startlingly human touches.

A mysterious ancient cemetery with Roman sarcophagi and Lycian inscriptions.

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

Temple complex that once housed the famous statue of Nike.

The partially submerged ruins of a white marble quarry used in ancient Greece for over 1,200 years.

This tower is all that remains of the mosque that once stood in the center of the city, before it was destroyed by fire in 1941.

The rocky remains of an ancient Greek forest.

A miniature desert appears out of nowhere on the lush isle of Lemnos, like something out of a Greek myth.

An alien landscape on the banks of the Aegean Sea.

This famous city eluded concrete detection until the early 2000's.

This vacant station is a relic of harvest processing techniques of the mid-20th century.

Locals often dress this effigy of Traverse City's founder in festive outfits.