Tucked into the Shawnee Hills in southern Illinois about 10 miles south-southeast of
Carbondale in
Jackson County, 1500-acre Giant City State Park tells a geological tale 315 million years old. The rectangular joint pattern of the area's Pennsylvanian bedrock, called Pounds sandstone, is the basis for the park's unusual rock formations including "Canyon Stairway" and "Devil's Stand Table" which, to early settlers, reportedly looked like the streets of a "giant city". In addition, "Old Stone Fort" was constructed by ancients up to 12,000 years ago.
