Morro Bay with Morro Rock State Historic Landmark, sometimes referred to as the "Gibraltar of the Pacific", in the background. Named “El Morro” by Portuguese Explorer Juan Rodriguez Cabrillo in 1542. “Morro” is the Spanish name for crown. Formed 23 million years ago from plugs of long-extinct volcanoes. California Registered Historical Landmark #821. State Landmark #801 (1968). Member of the “Nine Sisters” of volcanic plugs in San Luis Obispo County, CA. Protected home of nesting Peregrine Falcons.