Incredible places: A window onto extraordinary landscapes on Earth

The Coral Triangle is an extremely biodiverse patch of ocean around the Philippines and Papua New Guinea. Its relatively murky waters appear to shield it against climate change — for now.

The Cairo Fossil Forest is the second oldest in the world. These forests mark a turning point in Earth's history because they changed the composition of the atmosphere, scientists say.

The Narusawa Ice Cave is a natural lava tunnel that formed during a violent eruption of Mount Fuji in A.D. 864. Every winter, the cave grows giant ice pillars due to its freezing temperatures.

The Vanishing Lake in Northern Ireland's County Antrim can be full in the morning and empty a few hours later, thanks to an underground drainage system that scientists still don't fully grasp.

Three Whale Rock is a geological formation and tourist attraction in Thailand's Phu Sing Forest Park that looks remarkably like a small family of whales.

Mount Thor, also known as Thor Peak, is a mountain in Nunavut, Canada with the largest vertical drop in the world — a terrifying escarpment with an average overhang of 15 degrees from vertical.

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.