This National Park Rocks
Pinnacles National Park is one of our best idea's newest national park only having been established in 2013, and its 26,606 acres are a scenic slice of California that drew over 206,000 visitors in 2015. The Pinnacles themselves are rhyolite and andesite rocks that crown a high ridge that's the centerpiece of the park. They are fun to look at from afar and up close, and many visit for climbing adventures. The vegetation is the typical oak-pine-chaparral mosaic that covers most of the Coast Range from the Bay Area to Ventura County. As would be expected from the vegetation this hike is best done during cool weather. It gets Arizona hot here in the summer, and there is virtually no shade except in the caves in Bear Gulch.
This hike starts at the Bear Creek Picnic area, and the prospective hiker will probably have to take a shuttle to this spot from the Visitor Center further down Bear Creek Gulch. One starts in this deep canyon that only gives fleeting glimpses of the spectacular rocks above. The well marked trail starts on the north side of the road just past the parking area, and parallels the road for a few hundred yards until it enters a shaded oak grove that contains the best picnic spots. The trail continues up the gulch until it reaches a tunnel, and this is where the adventure begins.
The tunnel leads into a dry little cave that isn't all that interesting, but the trail continues up through a series of small caves alongside running water (at least it did on April 3, 2016) frequently making use of stairs with railings. This section can be annoying when the park is crowded, but it's good to just people watch. I was held up by a few families that looked to be just starting to explore outdoor recreation so that was cool. You will want either a headlamp or flashlight here because there are several stretches of pitch black, and many places to get injured. These caves were formed by large pieces of intact rock falling down from ridge tops, and coming to rest just below the bottom of Bear Gulch. Sediment has filled in many cracks so the caves appear to be bored through the earth.
The trail emerges about a mile from the start to a concrete staircase that heads up to the top of the small dam that holds Bear Gulch Reservoir. Climb the stairs and go across the dam to a number of small areas that are perfect for a small gathering. I don't know if swimming is allowed in Bear Gulch Reservoir, but that does activity does not look like a good idea. Just think about swimming in water that looks like chocolate milk with many things floating in it. There are great views on a social trail that heads west for a few tenths of a mile about 100' above the south side of the reservoir.
Return to the dam and take the Rim Trail as it climbs above the west side of Bear Gulch. The views get more spectacular with every step, and there are many places to take a short detour for a vista. The half-mile-long Rim Trail may seem longer than it is due to its many vistas, but it ends at the High Peak Trail. Go right here on the High Peaks Trail as the hike continues to climb ever upward. Hike through the chaparral as the trail climbs 900' in 2 miles to an outhouse and its junction with the Juniper Canyon Trail. This part of the trail has great views southeast to the Little Pinnacles and Mount Defiance as the southern highlands of The Pinnacles make their way up to North and South Chalone peaks.
The High Peaks Trail reaches the upper end of the Juniper Canyon Trail about 3.5 miles into the trip at a high point with a restroom. There isn't a road here, and the restroom only has vault toilets, but expect a lot of people here. There is a huge rock just south of the restroom that is frequently conquered for great views, and even a novice hiker can get up and down. There is a higher rock east of the restroom along the High Peaks Trail that also provides great views. The High Peaks Trail continues on the west side of the top of the jagged ridge for 3/4 mile until it reaches a junction with the Tunnel Trail heading up from the Juniper Canyon Trail.
This part of the hike has chaparral about 6' high. It's not as lush as the vegetation found on Point Reyes, but more closely resembles what one would find on Mount Diablo. The final ridge top section of this hike is when one travels 2/3 mile to the Condor Gulch Trail branching off to the right. Condor Gulch winds down its namesake drainage, first traveling through dry chaparral until it heads through riparian woodland below the overlook. The Condor Gulch Overlook is a small rock outcropping that narrows the drainage so water collects in small pools. Frogs were chirping when I was there one late afternoon, and I suspect this spot is great place to see wildlife.
The segment of the hike on the Condor Gulch Trail from the High Peaks Trail is about 1 and 3/4 mile from High Peaks, and is pretty mellow. There aren't any steep sections, and the descent into a riparian area is a treat. The oak trees become larger, California bay makes its appearance, and the signs of civilization appear as it always does where water collects. Soon enough one is back at the Bear Gulch Picnic Area waiting for the shuttle.
WARNING! Hiking and outdoor related sports can be dangerous. Be responsible and prepare for the trip. Study the area you are entering and plan accordingly. Dress for the current and unexpected weather changes. Take plenty of water. Never go alone. Make an itinerary with your plan(s), route(s), destination(s) and expected return time. Give your itinerary to trusted family and/or friends.