Santa Cruz Island is one of five within Channel Islands National Park. Here are pristine beaches, rugged mountains, lonely canyons, grass covered hills, and some animals and plants that you have never seen before. This island is a miniature of what southern California looked like over 100 years ago. The largest island in the national park, with 61,972 acres, Santa Cruz is 22 miles long and from two to six miles wide. A central valley splits the island along the Santa Cruz Island fault, with volcanic rock on the north and older sedimentary rock on the south. The Nature Conservancy and the National Park Service preserve and protect the island. It contains Painted Cave, one on the world’s largest sea caves.