Skip’s Punchbowl is a littoral sinkhole along the California Coastal Trail in Mendocino County, on the Noyo Headlands about one mile (1.6 km) south-southwest of Fort Bragg and 0.6 miles (1 km) west of Noyo, California. The feature is named after Skip Wollenberg, a geologist at Lawrence Berkeley Laboratory. For more than a century this stretch of coastal bluff sat locked behind the gates of a lumber mill, off-limits to the public. It now lies within the roughly 100-acre (40 ha) Noyo Headlands Park, built on the former Georgia-Pacific mill site and reached by a new stretch of the Coastal Trail, which also passes sea arches, tide pools, and headlands popular with whale- and bird-watchers.

The headland was once part of the Mendocino Indian Reservation, established in the spring of 1856 by the federal Bureau of Indian Affairs, one of California’s earliest reservations for the resettlement of Native Americans. Its roughly 25,000 acres (10,117 ha) were home mainly to the Pomo, a hunter-gatherer people of the northern California coast, alongside the Yuki, Wappo, Salan Pomo, Southern Pomo, Whilkut, and others. In the summer of 1857 the U.S. Army established Fort Bragg about 1.5 miles (2.4 km) north of the Noyo River, officially dated June 11th, to maintain order on the reservation and control its Native inhabitants. In June 1862 federal troops left to fight in the Civil War, replaced by California volunteers. In 1864 the reservation’s remaining residents were forcibly relocated to the Round Valley Indian Reservation. The Mendocino Indian Reservation was discontinued in March 1866, and the land was opened to settlers three years later.

Littoral sinkholes such as this are products of marine erosion, formed when a sea cave‘s roof collapses or its chamber gradually wears away, opening a shaft to the surface. Unlike inland sinkholes, which usually form through the dissolution of soluble rock, littoral ones almost always result from mechanical erosion and collapse rather than chemical weathering. The cave beneath typically retains a seaward entrance, and the roof most often gives way at the chamber’s most distal point, farthest from the sea, producing the deep, cylindrical basin, or “punchbowl,” characteristic of these features. Read more here and here. Explore more of Skip’s Punchbowl and Noyo Headlands here: