Pinnacles National Park is a national park of the United States protecting a mountainous area located east of the Salinas Valley in Central California, about five miles (8 km) east of Soledad and 80 miles (130 km) southeast of San Jose.

The park's namesakes are the eroded leftovers of the western half of an extinct volcano that has moved 200 miles (320 km) from its original location on the San Andreas Fault, embedded in a portion of the California Pacific Coast Ranges.

The national park is divided by the rock formations into East and West Divisions, connected only by foot trails.

Park lands are prime habitat for prairie falcons and are a release site for California condors that have been hatched in captivity.

Native Americans in the Pinnacles region comprised the Chalon and Mutsun groups of the Ohlone people, who left stone artifacts in the park.

The establishment of a Spanish mission at Soledad hastened the area's native depopulation through disease and dispersion.

Archaeological surveys have found 13 sites inhabited by Native Americans, 12 of which antedate the establishment of the missions.

[7] Interest in the area rose to the point that the Hollister Free Lance sent a reporter to the Pinnacles, followed two months later by a party of local officials.

Hain was a homesteader who arrived in the Pinnacles area in 1891 from Michigan, following his parents and eight siblings to Bear Valley.

Hain's efforts resulted in a 1904 visit by Stanford president David Starr Jordan, who contacted Fresno Congressman James C. Needham.

[12] Pinchot, who was primarily interested in the management of forests for productive use rather than for preservation, advocated the use of the recently passed Antiquities Act to designate the scenic core of the area as Pinnacles National Monument, which was done by Roosevelt on January 16, 1908.

In 1908 President Theodore Roosevelt created Pinnacles National Monument with the power given him in the Antiquities Act of 1906.

Lewis had a difficult trip and stayed only 45 minutes, and his report included a recommendation that the monument be abandoned, since the most scenic sections were in private hands.

[22] Following a visit by NPS assistant director Horace M. Albright, money was appropriated to build a ranger's cabin,[23] completed in 1929,[24] while facilities within the caves were improved.

[25] In 1929, condemnation proceedings were filed against private landowners in and around the park, including the mining company, seeking 1,286.27 acres (520.54 ha).

An expansion proclamation by President Herbert Hoover in 1931 added 1,926.35 acres (779.57 ha) of land donated by San Benito County.

According to the United States Department of Agriculture, the Plant Hardiness zone at the Painted Desert Visitor Center (1056 ft / 322 m) is 8b with an average annual extreme minimum temperature of 19.3 °F (-7.1 °C).

The movement of the Pacific Plate along the San Andreas Fault split a section of rock off from the main body of the volcano and moved it 195 miles (314 km) to the northwest.

[46] The rock formations are andesite and rhyolite, forming a dropped fault block embedded in the Gabilan Range.

Deep, narrow gorges and shear fractures were transformed into caves by large chunks of rock falling from above and wedging into the cracks, leaving an open area below.

[46] Since the Pinnacles were moved to this area, the San Andreas Fault has shifted four miles (6.4 km) to the east of the park.

[46] The establishment of the relative movement between the Pinnacles and the Neenach rocks was a significant factor in the acceptance of plate tectonics in geology.

[47] Seismic activity is frequent in the park, and United States Geological Survey maintains two seismometers within the boundaries.

[46] Native animals, now locally extinct from most of central California, included tule elk and pronghorn.

[49] Mammals and birds that inhabit this park include prairie falcon, coyote, skunk, great horned owl, bobcat, California quail, raccoon, wild turkey, gray fox, golden eagle, and cougar.

The culmination of a twenty-year, $1.6 million effort had succeeded in eradicating pigs from the main area of the park.

Monitoring for potential breaks and breaches in the fence is performed to ensure that the pigs do not return to the park.

Cooler portions of the park have higher proportions of pines and oaks, together with California buckeye, hollyleaf cherry, and coffeeberry.

When the region was inhabited by Native Americans, they used fire as a tool to encourage the growth of preferred food sources, and to herd small game during hunting.

[65][66] These caves house breeding colonies for Townsend's big-eared bat and are closed during pupping season.