The Midway-Sunset Oil Field is a large oil field in Kern County, San Joaquin Valley, California in the United States. It is the largest known oilfield in California and the third largest in the United States. The field was discovered in 1894, and through the end of 2006 had produced close to of oil. At the end of 2008 its estimated reserves amounted to approximately , 18% of California's estimated total. Setting The oil field runs southeast to northwest, with a length of approximately and a width of , from east of Maricopa to south of McKittrick, paralleling the Temblor Range to the southwest. Most of the oil field is in the Midway Valley and the northeastern foothills of the Temblor Range. To the northeast are the Buena Vista Hills, paralleling the Midway Valley and the Temblors; the mostly exhausted, and partially abandoned Buena Vista Oil Field lies beneath this adjacent low range of hills. State Route 33 runs along the axis of the Midway-Sunset for much of its length, and the towns of Taft, Maricopa, and Fellows are built directly on the oil field. Other oil fields along Route 33 going northwest within Kern County include the Cymric Oil Field, McKittrick Oil Field, and the large South Belridge Oil Field. Route 33 is not the only public road through the field: roughly paralleling 33, but closer to the Temblor Range, is Midoil Road, which winds through the field and along its southwestern boundary. The road commences from Taft Heights, passes through Fellows, and joins Mocal Road, which passes through the most densely developed part of the field, and rejoins Route 33 just south of Derby Acres. Crocker Springs Road, which passes over the Temblor Range to the Carrizo Plain, intersects Mocal Road about south of its intersection with Route 33. Another public road that passes through part of the Midway-Sunset Field is Petroleum Club Road, which runs southeast from Taft, and passes the site of the Lakeview Gusher. Geology While the Midway-Sunset field is a large contiguous area covering more than , it comprises 22 identifiable and separately-named reservoirs in six geologic formations, ranging in age from the Pleistocene Tulare Formation (the most recent geologically, the closest to the surface, and the first to be discovered), to the Temblor Formation, of Miocene age (the oldest, and one of the last to be discovered). Throughout the field, the Tulare is