Carrizo Badlands, Arroyo Tapiado Wash - There are Mud Caves in the Arroyo Tapiado wash located in the four-wheel-drive country of Carrizo Badlands within Anza-Borrego Desert State Park, California. Cracks created by water erosion have created the caves, some caves are reported to be 1000 feet long and up to 35 feet wide. Many caves have skylights created when the ceilings have collapsed. Surveys of the caves over periods of years show they are constantly changing. Walking on top reveals many sinkholes and areas of instability where one can fall into a hidden crack. It is best to connect with a local caving group and follow their safety recommendations when entering the caves, people have died exploring the caves.