This African beach is home to thousands of rare mainland penguins that are known for their annoying voice.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

This rugged area of red rocks and arches is often considered one of the most beautiful places on Earth.

Giant pinnacles in the sun-scorched lands of Southern Utah have been nicknamed "white ghosts."

Ancestral Puebloan ruins, natural arches, and box canyons abound in this seldom-visited corner of Monument Valley Navajo Tribal Park.

This secluded aqua waterfall in the Grand Canyon is the perfect swimming hole, and the Havasupai tribe's fiercely protected natural wonder.

Dramatic river bend surrounds a natural red-rocked pedestal.

Most-visited and most-photographed slot canyon in the American Southwest.

The largest dune field in the Mojave offers a chance of hearing the 'singing sands.'

Quite simply the largest tree in the world (by volume).

Four hundred granite steps were built into this massive rock by the National Park Service.

The rocks in this arid basin leave trails of movement behind them.

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.

This small group of sand dunes manages to pack in a strange rainbow of colors.

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

After millennia of erosion by sand and churning water this Brazilian valley now looks like a lunar fantasy.

This huge pile of volcanic boulders hides a stunning network of secret grottoes.

These jagged limestone blades cut out through the canopy of the jungles of Borneo.

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

See massive fossils that are over 200 million years old in northeastern Arizona.

This quaint Italian town keeps losing ground as the sides of its plateau slowly erode.

This gracefully curving formation looks like a massive wave that was suddenly turned to stone.

Raging waters have created a strange geological site that looks like something off of a progressive rock album cover.

The caldera of this mini-volcano has been turned into a naturally heated mud bath.