Bowling Ball Beach, Coastal beach with geological formations in Mendocino County, California.

Bowling Ball Beach is a coastal area in Mendocino County, California, where round sandstone blocks are scattered across the sand and shallow water. These spherical formations developed through natural erosion and create an unusual geological feature that sets this shoreline apart from typical California beaches.

The spherical blocks formed over millions of years as ocean waves carved away softer rock layers around harder sandstone concretions. This natural erosion process continued over long periods and created the formations visible today.

The name comes from the round concretions, which resemble bowling balls and appear only at low tide. The beach lies within Schooner Gulch State Beach in Mendocino County. Similar concretions occur in North Dakota and New Zealand, but here thousands sit evenly spaced on the sand.

Visitors should plan their arrival according to tide tables and come during low tide to see the formations on the seafloor and in the sand. A visit in early morning or late afternoon hours offers the best light for taking photographs.

The spheres are sandstone concretions, cemented masses that grew inside softer sedimentary layers; the surrounding rock eroded away and left them on the sand. The same phenomenon occurs at sites in North Dakota and New Zealand. The beach lies within Schooner Gulch State Beach, and the concretions are exposed only at low tide.