Explore the unique underground labyrinth of Wind Cave National Park, known for its boxwork formations and one of the longest caves in the world
Explore hydrothermal vents, lava domes, lakes, and volcanic peaks in Lassen Volcanic National Park.
Experience salt flats, dunes, canyons, mountains, and extreme desert landscapes in Death Valley National Park.
Walk lava landscapes and see active volcanic terrain in Hawaiสปi Volcanoes National Park.
Forest of razor-sharp limestone, UNESCO-listed.
A "mini Grand Canyon" of red rock.
The one Kenyan park you can explore by bike, pedalling past zebra and giraffe to the red cliffs and gorge that inspired The Lion King.
Trails and tunnels along a marble canyon so narrow the cliffs nearly touch, with the Eternal Spring Shrine over a waterfall.
Six sapphire lakes held by natural travertine dams in the Hindu Kush โ Afghanistanโs first national park.
Home of Son Doong, the worldโs largest cave, plus Paradise Cave and boat trips into the river cave of Phong Nha itself.
Gunung Muluโs vast cave system, including the Deer Cave and its nightly bat exodus.
Rift-valley site of the worldโs oldest parliament, where the tectonic plates pull apart.
Drift between the American and Eurasian tectonic plates in gin-clear glacial water.
See fossilized trees, painted desert badlands, ancient sites, and Triassic landscapes in Petrified Forest National Park.
Descend into vast limestone caves and desert landscapes at Carlsbad Caverns National Park.
See the steep dark cliffs and narrow river-carved gorge of Black Canyon of the Gunnison National Park.
Explore sandstone domes, cliffs, canyons, and the Waterpocket Fold in Capitol Reef National Park.
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