Major tourist destination known for its bubbling mud-pools and hot thermal springs.

A galaxy of glowworms—larvae of a gnat—hides deep in the belly of these caves.

Dolphins, ancient clams and hundreds of waterfalls make this one of the world's top tourist destinations.

An encyclopedic collection of mammal penises.

This replica of the Greek structure is in the heart of Nashville.

Tubing through a cave lit with glowworms is a magical underground experience.

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

Built by a king and rebuilt by an emperor, this aqueduct transported water for 1,200 years to this ancient Mediterranean hub.

Hidden beneath a washing machine in a fake kibbutz, this secret bullet factory has been preserved as a museum.

Descend 2,030 years into the past in an ancient tunnel built to support Jerusalem's most famous wall.

This daunting 1st century fortress was purportedly the site of one of the most dramatic revolts of the Jewish-Roman wars.

Come for the flowers, stay for the bats!

The last remaining attraction from Paragon Park.

Plans for this peninsula included houses, the United Nations Headquarters, and a nuclear power plant. When none of them worked out, it became an expansive park.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

Plymouth's huge yet little-known memorial to the Pilgrims.

This museum shines a light on the true Pilgrim experience in North America.

This 38-drawer structure claims the superlative title, but it isn't the world's only giant filing cabinet.