Great Salt Plains in Jet, Oklahoma

Millennia ago, a shallow sea covered this area in Oklahoma. Its legacy is the Great Salt Plains, a salt lake and 11,000 acres of salt flats atop a saltwater aquifer in the middle of the Great Plains. The area is now a state park and a wildlife refuge. More than 300 protected species of birds call the region home or stop by during seasonal migrations, and large game animals seek out the salt plains for nutrients, which historically made it a coveted hunting area among Indigenous people.

The most unique trait of the Great Salt Plains hides just underground: a rare form of selenite crystal called hourglass selenite, so called because the crystal tapers at the middle to form an hourglass shape. (They are also the state crystal of Oklahoma!) The Salt Plains are the only place in the world where such crystals form, and from April to October the public can hunt for them in the park and dig up these geological wonders.