Henry Coe State Park is the only park in the Bay Area that allows camp-where-you-wanna backpacking. All the rest require reservations, and good luck getting a Saturday night at Big Basin or Sunol Wilderness if you haven’t paid for your site a couple months in advance.
If you’ve never been to Henry Coe, be warned: the hills that make the park so wonderful often must be traversed by old fire roads built for combustion-engine vehicles. While the park has a fair number of single-tracks that are nicely zigzagged, most destinations require serious, punishing climbs. This scares off a lot of people, but it leaves more park for the rest of us. Most famous Henry Coe saying: “People don’t come to Coe to train for the Sierra; the go to the Sierra to train for Coe.”
Henry Coe has a bunch of established campsites at Los Cruzeros and Poverty Flat, but these’ll also fill up fast on a weekend. Forget about the prized campground at China Hole on a weekend, somebody always seems to get there first (the other reason to forget China Hole is that it gets well-digger’s-ass cold in that canyon overnight). There’s a nice little campsite called Hidden Spring that I stayed at one autumn weekend a few years back that’s quiet and off the beaten paths. This page at Coepark.org describes all the established sites.
The main advantage of established sites: most have a spring or creek nearby. The main disadvantage: near major trails with lots of hikers and campers tramping through.
Henry Coe’s Hunting Hollow entrance is my favorite trailhead for backpacking — though the remote Dowdy Ranch entrance has its charms (I haven’t tried it yet; it opens May 2 for the 2009 season). Hunting Hollow starts out in a valley where you can either take a gradual slog to the top of the nearby ridges, or you can just pick a ridge nearby and start fighting your way up it.
Camping near Coit and Kelly lakes is an excellent option, though they do attract a fair number of fellow campers (and they require 8 to 10 miles of strenuous hiking to reach them). Also, rangers try to limit the number of campers near the lakes. I camped next to a nice little pond near Coit Lake.
The Grizzly Gulch Trail also has a couple nice ponds worth checking out. I saw a bobcat once along this trail, which is one of the nicest at Coe.
Here’s a Google Map of the major Henry Coe trailheads and lakes.
View Henry Coe State Park Lakes and Trailheads in a larger map
The dot at the upper left is the Dunne Avenue/Park Headquarters entrance. Bottom left is Hidden Hollow; far right is Dowdy Ranch. From top to bottom in the middle are Mississippi, Coit and Kelly lakes.
Henry Coe’s Orestimba Wilderness is worth a look if you’re an ultralighter who can put in over 15 miles in one day.
You’ll want trail maps. Many options at Coepark.org. The big, plastic-coated map most people buy is nice to have, but it’s heavy. They’re available for $8.50 at the Dunne Avenue park HQ.
Henry Coe usually can be backpacked from late October through early June. The rest of the summer will be far too hot, and most of the creeks will be dry. Always ask the rangers about how the springs are running before you head out. You don’t want want to be 12 miles from a trailhead with no water at Henry Coe.
Backcountry camping is $3 a night per person, plus the cost of parking ($5 a day at Headquarters or Dowdy Ranch, $4 a day at Hunting Hollow).