North Peak at Mount Diablo State Park

The hike starts from the Mount Diablo State Park trailhead in the East Bay suburb of Clayton (see driving directions for getting there). There's no fee to park here, but you'll spend plenty of energy on the hike up.

Just past the trailhead gate, Donner Canyon Trail begins on your left. Take this trail and stay on it till it ends after about 1.5 miles at Cardinet Oaks Road. Climbing on this section is fairly mild; it gets mean soon enough.

Go left on Cardinet Oaks Road, which dips down to a creek crossing (which may be ankle deep during rainy season), then start climbing in earnest. After about 1.2 miles on Cardinet Oaks, the Olympia Trail marker appears on your right. Turn there.

This is when the real climbing starts. Olympia Trail zizgags up the hillside on a narrow single-track, then enters open terrain. After about a half-mile you'll hit the Zippe Trail junction, a left turn that'll get you to the Mount Olympia summit in about a half-mile. Your other option is to stay on Mount Olympia Trail, which is slightly longer. Both are calf-burner steep, so it's really a coin flip on which is the best route.

After you've rested up at the Mount Olympia summit, it's on to North Peak. The Peak dominates the landscape so you know which way to go: just find the North Peak Trail and start walking.

North Peak Trail is a narrow, .8-mile stretch of single-track on a steep, rocky slope. This is one of my favorite Bay Area trails, but don't be lulled by the scenery: a slip here could be a bone-breaker.

Once you get to North Peak Road, it's a left turn and another steep climb to the summit. The radio towers might not seem like much of an improvement on the masses of humanity at the main summit, but they reassure me that I'm not the only one crazy enough to be up here.

From the North Peak summit it's about .8 mile down to Prospector's Gap, where you have three choices, depending on how strong you feel:

a) If you're gassed, take Prospector's Gap Road, which is mostly downhill, for 1.3 mile to Meridian Ridge Road, then bear left and go another .3 mile to Murchio Gap, the next major trail junction on this route.

b) If you've got a bit more climb in your legs, the Bald Ridge Trail offers a much prettier 1.3-mile route to Murchio Gap.

c) If your legs feel fine, it's 1.5 miles (one way) to the main Diablo summit, which has running water and flush toilets. Mind you it's 800 feet more elevation gain.

From Murchio Gap, it's all downhill for 2.6 miles along the Back Creek Trail, which tracks due north from the gap (a left turn if you're facing north). Back Creek Trail is another Mount Diablo gem, steep and rocky in parts, but generally a pleasure to hike.

Back Creek Trail takes you back where you started; expect to be exhausted but at least a bit elated at finishing one of the region's essential hikes.