The first declared National Monument in the United States.

Native Americans built this circle of stones, which was used to predict astronomical events.

Enormous array of antennae fill a desert valley.

Cold storage for agricultural biodiversity.

NASA's leading space science lab started by a co-founder with deep ties to the occult.

Large Hadron Collider and the Birthplace of World Wide Web.

An auroral research program that superheats the ionosphere.

Display that gathers the basic elements of the universe in one convenient location.

A clock designed to run with perfect accuracy for 10,000 years.

France's national museum of scientific and industrial instruments.

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

Two waterfalls flow down the cliff faces decorated with rare natural basalt columns.

Visit this playground of waterfalls, caves and sinkholes.

A lake formed in the basin of a massive impact crater takes the shape of an unbroken ring when viewed from above.

Thousands of Haitians travel to the waterfalls to ask the Virgin Mary of Mount Carmel and her voodoo counterpart Erzulie for healing in a yearly pilgrimage.

The largest pool at its elevation sits on top of one of the most expensive resorts in the world.

Mother Nature outdoes herself with this stunningly beautiful set of caves carved into marble.

The world's first and only natural nuclear reactor.

The true jewel of Africa's west coast known as "Africa's Last Eden."

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

A breathtaking canyon offers stunning views and frightful pathways through an ecological paradise.

An emerald-green grotto just a short trip from Austin.

This Tang Dynasty behemoth is the biggest Buddha in the world.

Rock-cut caves and 7,000 Buddhist sculptures carved into the nearly sheer face of a sandstone mountain.