Mt Olympia

Nice trails, but NO PUBLIC ACCESS by Trail Ride Road (publicly maintained trails in a state park are apparently private property).

Awesome trails with very few people

Except it was the Falls Trail. Most excellent condition also. No water yet of course.

Had a wonderful time hiking Mt. Diablo State Park's four peaks: Mt. Olympia, North Peak, Summit Peak, and Eagle Peak. Each of the four peaks offer their own sweeping vistas of the surrounding areas, including views of San Pablo and Suisun Bays, the Delta, the Central Valley, the hills leading towards the 580 corridor going towards Tracy, the 680 corridor going from Walnut Creek towards Dublin, the East Bay hills, and beyond. Roughly 15 mile hike do-able in eight hours (including breaks) if you're in decent shape and enjoy hiking. Plenty of information available on the internet if you're going to do some homework before you attempt this hike. Would definitely recommend this hike.

(Olympia trail) It's a moderate to hard hike. It gets really really steep in the last 0.5 mile (1.5k ft elevation gain). Carry at least 2 bottles of water. Use really good hiking boots and poles. You *may* not need poles while going up, but man.. you really can't come down without it. I forgot but had more than 10 instances where I could have easily fallen into the bushes/off the trail. This is because of steepness and gravel on the trail.