The meteor that sealed the fate of the dinosaurs landed at this site, one of the largest impact craters in the world.

One of the few places where you can visit a cenote and Maya ruins at the same time.

A hacienda that features all things uniquely Yucatán.

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

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

Found down a long dirt road, a sacred Mexican cenote and 18th-century hacienda remain hidden.

This popular cave pool is truly magical, despite the crowds.

Beach instrument turned bed and breakfast.

Three sinkholes filled with warm, crystal-clear water reached by a horse-driven cart on an old train track through the jungle.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

Located in the thermoelectric factory that once powered the entire city, this Portuguese museum is shockingly fascinating.

This Slovakian statue of an emerging sewer worker might just be a bronze peeping tom.

A museum in the childhood house of a medical pioneer.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

Museum dedicated to the terror regimes of Hungary.

The first museum in the world devoted to sexual gadgetry.

Dedicated to the unsung history of human waste.

A turn of the century building boasting some of the most beautiful art nouveau architecture in Prague.

The last municipal pneumatic post system in the world was in operation for over 100 years, and may run again.

A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.

A mocking tribute to the past and modern leadership of Prague.

A controversial artwork draws attention to the dark history of Prague's "Suicide Bridge."

Living trees form the structure of an open-air palace.

A small man-controlled waterfall powers an Art Nouveau elevator and is accessed via narrow gauge, solar-powered tramway.