Jeffers Petroglyphs — Wikipedia

The Jeffers Petroglyphs site is an outcrop in southwestern Minnesota with pre-contact Native American petroglyphs. The petroglyphs are pecked into rock of the Red Rock Ridge, a 23-mile (37 km)-long Sioux quartzite outcrop that extends from Watonwan County, Minnesota to Brown County, Minnesota. The exposed surface is approximately 150 by 650 feet (50 by 200 m) and surrounded by virgin prairie.