Spelunking Challenge: Karst Marathon

Karst is a fascinating type of landscape that contains caves, sinkholes, and underground rivers. Karst caves are also called “solution” caves, and are created by the erosion of rock (usually limestone) over time, as rainwater flows through it.

Karst landscapes get their name from the Karst region in Slovenia, an area of arid limestone plateaus. But you can find karst terrain all over the world!

The world’s longest karst cave system is found in Mammoth Cave National Park, a park located within the Central Kentucky Karst. With over 405 miles (651 km) of mapped caverns, this fascinating and diverse area features amazing mineral deposits, fossils, and is home to at least 160 species of animals, including the Kentucky Cave Shrimp, an eyeless troglobite endemic to the area.

Phong Nha – Kẻ Bàng National Park is another area with impressive karst topogrophy. This Vietnamese national park is in one of the largest limestone regions in the world, and is the oldest major karst in Asia. It has the world’s largest underground river, as well as the world’s largest cave, Son Doong Cave, with a volume of 38.5 million cubic metres.

A third example of cool karst features is Xiaozhai Tiankeng, also known as the “Xiaozhai Heavenly Pit,” located in Fengjie County in southern-central China. This massive sinkhole is the deepest in the world, measuring in at over 500 meters (1640 feet) deep. The sinkhole is surrounded by lush greenery, and was formed by a river which now sits in the depth of the pit.

These are just a few notable areas with amazing karst landscapes, but there are many more to explore around the world! While you think of your next spelunking adventure, join us in our next marathon adventure where we’ll try to complete a cell in just 24 hours!

Marathon Instructions:

Starting at 10:00 AM ET on 4/2, you will have 24 hours to complete one or more cells. Bonus & cell renaming information can be found in your in-game notifications.