Pinnacles National Monument was established on January 16, 1908, for the purpose of protecting its natural rock formations, known as Pinnacles Rocks, and the series of talus caves underlying them. The monument sits within one of the most complex and fascinating geologic terrains in North America, an area where rock masses have been sliced apart, transported for up to hundreds of miles, and then reassembled into a fantastic geologic mixture. The monument holds only half of an ancient volcano; the other half is found 195 miles to the southeast in northern Los Angeles County. The volcano was split apart and transported north by an early strand of the San Andreas Fault, known as the Chalone Creek Fault, which lies within the monument. The pinnacles inside the monument are composed mainly of volcanic breccia, a mixture of angular blocks of volcanic lava, pumice, and ash. The occurrence of the pinnacles within the monument is unusual, as some of these volcanic rocks also contain marine fossils.

Since 1908, the boundaries of the monument have been enlarged on five occasions by presidential proclamations issued pursuant to the Antiquities Act (34 Stat. 225, 16 U.S.C. 431). Proclamation 1660 of May 7, 1923, added 562 acres to include additional natural formations with a series of caves underlying them. Proclamation 1704 of July 2, 1924, added adjoining lands that included a spring of water and valuable camping sites. Proclamation 1948 of April 13, 1931, added 1,926 acres that held additional features of scientific and educational interest and for administrative purposes. For these same purposes, the boundary was later expanded on July 11, 1933 (Proclamation 2050). Proclamation 2528 of December 5, 1941, added additional lands adjoining Pinnacles National Monument in order to protect more objects of scientific interest in the monument area. The boundary of the monument was further expanded by statute on October 20, 1976 (Public Law 94-567, 90 Stat. 2693).

The boundary enlargement effected by this proclamation is central to the continued preservation of the Pinnacles National Monument’s unique resources. In addition to containing pieces of the same faults that created the tremendous geological formations throughout the monument, the expansion lands hold part of the headwaters that drain into the basin of the monument. Over millions of years, flash floods and stream currents have helped to sculpt the land’s natural features. Additionally, these lands contain a biological system that must be protected if the wild character and ecosystem of the monument are to be preserved. The geologic formations provide a stellar habitat for important and sometimes fragile biological resources. For example, raptor populations, including prairie falcons, golden eagles, red-shouldered hawks, Cooper’s hawks, harriers, white-tailed kites, long-eared owls, and red-tailed hawks, nest on the rocky formations and forage in the broad watershed. The lands within the expansion area contain steep, rugged slopes surrounding small canyons. Shallow rocky soils, gravel creek beds, and steeply rising topography combine to create a dynamic flood environment. The lands preserve a complex association of plant communities characteristic of the chaparral. Along the watercourses, live-oaks, buckeyes, and sycamore grow. Blue oak woodlands and grasslands occur on the deepest soils. Creeks that flow in and out of the existing monument and the expansion lands provide highly valuable riparian habitat for wildlife. The western pond turtle, two-striped garter snake, silvery legless lizard, threatened California red-legged frog, and California horned lizard inhabit these lands. By expanding the monument, these unique biological resources can be afforded more complete protection to maintain and enhance the ecosystems of the monument.

Section 2 of the Act of June 8, 1906 (34 Stat. 225, 16 U.S.C. 431) authorizes the President, in his discretion, to declare by public proclamation historic landmarks, historic and prehistoric structures, and other objects of historic or scientific interest that are situated upon the lands owned or controlled by the Government of the United States to be national monuments, and to reserve as a part thereof parcels of land, the limits of which in all cases shall be confined to the smallest area compatible with the proper care and management of the objects to be protected.

WHEREAS it appears that it would be in the public interest to reserve such lands as an addition to the Pinnacles National Monument:

NOW, THEREFORE, I, WILLIAM J. CLINTON, President of the United States of America, by the authority vested in me by section 2 of the Act of June 8, 1906 (34 Stat. 225, 16 U.S.C. 431), do proclaim that there are hereby set apart and reserved as an addition to the Pinnacles National Monument, for the purpose of care, management, and protection of the objects of scientific interest situated on lands within the said monument, all lands and interests in lands owned or controlled by the United States within the boundaries of the area described on the map entitled “Pinnacles National Monument Boundary Enlargement” attached to and forming a part of this proclamation. The Federal land and interests in land reserved consist of approximately 7,900 acres, which is the smallest area compatible with the proper care and management of the objects to be protected.

The enlargement of this monument is subject to valid existing rights.

All Federal lands and interests in lands within the boundaries of this monument are hereby appropriated and withdrawn from all forms of entry, location, selection, sale, leasing, or other disposition under the public land laws, including but not limited to withdrawal from location, entry, and patent under the mining laws, and from disposition under all laws relating to mineral and geothermal leasing, other than by exchange that furthers the protective purposes of the monument. Lands and interests in lands not owned by the United States shall be reserved as a part of the monument upon acquisition of title thereto by the United States.

There is hereby reserved, as of the date of this proclamation and subject to valid existing rights, a quantity of water sufficient to fulfill the purposes for which the monument is established. Nothing in this reservation shall be construed as a relinquishment or reduction of any water use or rights reserved or appropriated by the United States on or before the date of this proclamation.

The Secretary of the Interior shall manage the area being added to the monument through the National Park Service, under the same laws and regulations that apply to the rest of the monument, except that livestock grazing may be permitted in the area added by this proclamation.

Wilderness Study Areas included in the monument will continue to be managed under section 603(c) of the Federal Land Policy and Management Act of 1976 (43 U.S.C. 1701 et seq .).

Nothing in this proclamation shall be deemed to revoke any existing withdrawal, reservation, or appropriation; however, the national monument shall be the dominant reservation.

Warning is hereby given to all unauthorized persons not to appropriate, injure, destroy, or remove any feature of this monument and not to locate or settle upon any of the lands thereof.

IN WITNESS WHEREOF, I have hereunto set my hand this eleventh day of January, in the year of our Lord two thousand, and of the Independence of the United States of America the two hundred and twentieth.