The lakebed is a flat playa formed in an undrained basin. Silt and clay are deposited into this basin during periods of heavy rain. When the "lake" dries, a hard pan dry lakebed is left. This hard, smooth surface is ideal for the unique activities conducted at El Mirage. These include ultra-light aircraft and gyrocopter flying, model rocketry, remote control airplane flying, landsailing and straight track racing. Many private pilots land on the lakebed to spend the day. The surface character has attracted the interest of many filming companies. Several major movies have scenes filmed here. There is no speed limit on the open lakebed, but vehicle operators are responsible for their own safety, OHV rules and regulations, and knowing what is going on around them. The maximum speed limit is 15 miles per hour within 50 feet of camps and staging areas. During permitted events, special speed limits and traffic restrictions are posted. Please watch for these events. To maintain a smooth surface, the lakebed is closed when wet or muddy. The California Highway Patrol, San Bernardino County Sheriff, and BLM Rangers patrol the area to encourage safe use by visitors. Camping is permitted on the lakebed, but no more than 100 feet from the edge. This keeps the smooth center section of the lakebed clear for night riders.