Incredible places: A window onto extraordinary landscapes on Earth

Egypt's Whale Valley, or "Wadi Al-Hitan" in Arabic, holds more than 400 primitive whale skeletons that offer a snapshot of the evolution of these creatures from land-based to marine animals.

Taal Lake on Luzon Island in the Philippines is a volcanic crater lake with a rare geology of nested islands and water.

Lake Natron is a soda lake in northern Tanzania with a volcanic geology that maintains the water's pH around 10.5, which is almost as caustic as ammonia. Some life-forms thrive there nevertheless.

Giant groundsels are rare plants that grow up to 30 feet (9 meters) tall. They are endemic to the slopes of Mount Kilimanjaro, a dormant volcano in Tanzania and Africa's tallest mountain.

The Midcontinent Rift is a giant tear that formed in what is now the U.S. Midwest 1.1 billion years ago. Nicknamed North America's "broken heart," it is filled with solidified magma and lava.

Palau's Jellyfish Lake is home to millions of endemic golden jellies that live in the lake's top layer but never venture below 50 feet, where the water is saturated with poisonous gas.

Cerro El Cono is a solitary, pyramidal hill in the Peruvian Amazon rainforest whose origins remain mysterious and that holds spiritual significance for Indigenous people.

The Corryvreckan whirlpool is one of the largest whirlpools in the world, reaching speeds of 8.5 knots and producing a roaring sound that can be heard 10 miles away.

Iran's folded rocks are a colorful formation that is part of the Greater Caucasus mountains, which formed when the Eurasian tectonic plate collided with the Arabian plate millions of years ago.

Researchers have proposed many origins for a gravity anomaly in Wilkes Land, East Antarctica, but the latest evidence suggests the subglacial hole is an impact crater measuring 315 miles across.