Incredible places: A window onto extraordinary landscapes on Earth

Scientists first described the flooded cave in 2016 but determined its extraordinary extent years later.

Every year, record-seeking surfers and spectators descend on the small Portuguese town of Nazaré for the "big wave" season, when water can surge up to 100 feet (30 meters) tall.

Every winter, when sunlight hits at the right angle, visitors to Virginia's First Landing State Park are treated to a mesmerizing rainbow light show courtesy of the park's bald cypress swamp.

The growing "gateway to the underworld," officially known as the Batagay megaslump, is the largest megaslump in the world and exposes permafrost layers that are 650,000 years old.

Every winter and spring, great white sharks that usually dwell off the coast of California gather in a remote section of ocean the size of Colorado — and scientists are slowly piecing together why.

Al Naslaa is a rock formation in Saudi Arabia's northwestern desert consisting of two huge, symmetrical stone blocks that are separated by a mysterious gap and sit on small pedestals.

In Racetrack Playa, a dry lakebed in Death Valley National Park, meteorological conditions can push rocks weighing up to 700 pounds along the flat ground.

The Yarlung Tsangpo Grand Canyon is Earth's largest terrestrial canyon, stretching 314 miles long and almost 20,000 feet from top to bottom at its deepest point in the Tibet Autonomous Region.

The Salar de Uyuni desert is famous for its gleaming surface waters and hexagonal salt crust patterns, but below this otherworldly landscape lie about 11 million tons of highly sought-after lithium.

Lake Kivu, one of the African Great Lakes, sits along a tectonic plate boundary called the East African Rift, which is dotted with hot springs that feed carbon dioxide and methane into the water.