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

These winged Maya figures are the subject of speculation and conspiracies.

A mysterious, abandoned Chinese building in Mexico pays homage to the area's East Asian immigrants.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

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

This unreal Portuguese palace looks as though it's made from a pile of different castles.

One of the world's oldest and most massive living organisms is a grove of quaking aspens.

A fantastical bed and breakfast with magically unique rooms.

An explosion of natural color known as "the river that ran away from paradise."

This striking pig statue was part of a 1993 guerilla art project against racism.

A mysterious concrete hand reaches out from between the stones of Uniwersytecki bridge.

At 130 years old and 126 feet tall, it is the largest known example of the rare Torrey pine tree.

Colorful Native American paintings are hidden within this small cavern.

Coastal dunes, site of buried Egyptian movie set and former utopian colony.

An alley covered with 20 years of bubble gum.

A Mysterious Masonic tomb in San Luis Obispo.

A house built from trash known as the poor man's Hearst Castle.

This stretch of beach along California's central coast is a busy highway for the largest seal in the northern hemisphere.

The unbelievably opulent home built for an infamous newspaperman.

The walls of America's oldest masonry fort famously "swallowed" cannonballs.

What if the cure for all that ails you was as simple as repeated exposure to low-dose radon?

This beautiful natural train tunnel is said to grant the wishes of visiting lovebirds.

An Australian lake whose pink hue defies scientific explanation.

This magical grotto is adorned with a complex pattern of native seashells, minerals, and fragments of colored glass.