Although Pinnacles has only been a National Park since 2013 the geologic features it encompasses have been deemed worth protecting since 1908 when Pinnacles was designated as a National Monument. After 1908 the area of the National Monument grew as bits and pieces were acquired. What began as a 2500 acre protected area through Bear Valley is now a 26,000 acre area (16,000 of which is wilderness) preserving the valley, canyons, creeks and of course, the geology of the National Park. It is one of the few parks in the National Park System to feature Talus Caves large enough to walk through. Pinnacles offers hiking, rock climbing, night sky, wildflower and wildlife viewing or just an escape into nature for urbanites from the San Francisco and Monterey Bay areas. The best time to visit is Autumn, Winter or Spring. When the coastal climate turns blustery the Pinnacles' Mediterranean climate is no longer dangerously hot.
Talus caves are narrow canyons which have been covered over by large boulders to form a ceiling.
Getting there: Access to either the West or East Entrance of the park is via CA-146, but the highway is not a through road inside the park from one entrance to the other. CA-146 from the west is winding and narrow in places so not recommended for large vehicles, trailers or RVs. The gate at the West Entrance allows hikers to leave at any time but does not allow entry between sunset and sunrise. An Entrance Fee of $15.00/non-commercial vehicle is valid for 7 days.
About Pinnacles Campground: The campsites here were segregated into separate loops for tenters (80 sites) and RVs (30 sites) so generator noise was not a problem for tenters. The Loop roads were paved but the parking and tenting surfaces were hard-packed dirt with some holes dug by burrowing squirrels, each tent site had a food locker (ours had some ants). In each loop there was one bathroom building with two stalls, three sinks and mirrors but no electricity. Some sites, like 31, 32 and 37 had good shade but were also littered with tree debris. Quail, Scrub Jays, Squirrels and Mule Deer were common residents. Sites were large enough for several tents and semi-private from others in the loop. Near the Day Use Area at the East Entrance Visitor Center was a pool and shower house. We did not find AT&T cell signals anywhere in the park.
Pinnacles' geologic formation is complicated. Here is the simple version: The story began quite recently after continents had already formed as we know them today. The Pacific Ocean still reached far inland, not yet cut off by Coastal Ranges. Then plate tectonics made things interesting! The Farallon Plate began pushing under and raising up the North American Plate, forming the coastal range and starting the age of volcanoes in California.
The Pinnacles Volcano was born in Southern California near Los Angeles, eventually growing to an 8000-foot high volcano slightly smaller than Mount St. Helens. Once formed it set out to see the world, hitch-hiking north on the San Andreas Fault until it found a good home 195 miles away in a graben (aka ditch) where two-thirds of the Pinnacles Volcano settled between the San Andreas Fault and the smaller Pinnacles Fault. The partial volcano sank down into the graben and was protected until the fault ramparts eroded, exposing the volcano. In its senior years the volcano is eroding, often forming talus caves at its base. However, it is still moving with the San Andreas Fault, which slips north at about 1 inch per year.
The rock formations in Pinnacles N.P. are a unique combination of volcanic and sedimentary rock called Rhyolitic Breccia. Although climbing is allowed in the Machete Ridge area of the park, the rock is often weaker and more brittle than the granite or basalt in other parks. Some rock-climbing experience, good equipment and extra caution is advised here.
Diversity: With elevations of 824 feet at Chalone Creek up to 3304 feet on North Chalone Peak but only 16 inches of rain annually, the park protects a variety of habitats. California Condors soaring above the rocky pinnacles and cave-loving bats are just two of the more famous species living in the park. The 400 bee species found in the park represent the highest diversity per area of any other place in North America. The bees, birds, insects, mammals and reptiles can choose from woody evergreen shrubs in the chapparal, blue oaks and grey pines in the woodlands, meadows of grasses and wildflowers or riparian zones along creeks lush with mosses and ferns.
Native Peoples: Very little archaeological work has been done in Pinnacles. Most of today's knowledge of native peoples comes from the records kept by Spanish Missions in post-contact times. The Chalone and Mutsun tribes were found in the Pinnacles region. European diseases and drastic changes to their way of life as they "converted" to Mission life descimated the natives. Descendants of these people have established a partnership with the park to help manage cultural sites and add to the knowledge of the history of their ancestors.