Red Rock Coulee

The reddish boulders are sandstone concretions and are up to 2.5 meters in diameter.  They are among the largest in the world.  The boulders were formed in prehistoric seas as layers of sand, calcite and iron oxide collected around a nucleus formed by shells, leaves or bones.  Look carefully at the concretions- you may be able to see their “growth rings” (layers of sediment deposition) and fossilized shells, leaves or bones. There are eroded steep-sided coulees and a small upland of fescue-needle grass. In places, hoodoos (columns of bedrock) have formed. Plants nearby include gumbo primrose, sagebrush, juniper, prickly pear cactus, prairie crocus, and broomweed.  From the ground that feels like popcorn to the unique prairie plants and animals this is a great geological wonder to see.