Morro Rock

Morro Rock is a large volcanic plug, a mass of solidified dacite lava that once filled the conduit of an ancient volcano, standing roughly one hundred and seventy five meters high at the entrance to Morro Bay harbor on the central California coast. It is the northernmost and largest of the Nine Sisters, a chain of volcanic peaks stretching inland to San Luis Obispo, exposed over roughly twenty to twenty five million years as the softer surrounding rock eroded away. The rock is now closed to climbing to protect a nesting population of peregrine falcons.