Things to Do: Crystal DIG!! Crystal Dig at the Great Salt Plains State Park in Jet, Oklahoma: Season Open April 1st-October 15th Alabaster Caverns State Park Hiking, Cave tours & Bat watching at the Alabaster Caverns State Park in Freedom, Oklahoma Great Salt Plains Refuge Enjoy a hike or the salt plains at the Great Salt Plains Wildlife Refuge. Northwestern Oklahoma State University Catch one of the many sports that NWOSU offers in Alva, Oklahoma. Sod House Visit the Sod House in Aline, Oklahoma
