Complex sentence: The Racetrack Playa, located in Death Valley, California, features a geological phenomenon known as "sailing stones" that leave linear "racetrack" imprints as they slowly move across the surface without human or animal intervention.
Split into simpler sentences: The Racetrack Playa, located in Death Valley, California, features "sailing stones" that leave linear "racetrack" imprints. The stones slowly move across the surface, leaving a track as they go, without human or animal intervention.