OverviewMt. Isabel is a broad, brush covered peak 1 mile south of Mt. Hamilton and Copernicus Peak. It is easily viewed from San Jose as the dark, dome shaped mountain that looms to the right of Mt. Hamilton and the Lick Observatory. If viewed upon from San Jose, one might say that Mt. Hamilton appears taller than Mt. Isabel, but Mt. Isabel is actually 17 feet higher than the summit of Mt. Hamilton. This makes Mt. Isabel the second highest peak in Santa Clara County, after Copernicus Peak. An old, not-much traveled fireroad leads to the summit, which leads me to believe that this peak isn't hiked very much. The fact that the peak is on private property also, I assume, hinders hikers from bagging it. A summit log existed from Feb. 2006 until Spring 2007, when it was replaced with a note from the land owner warning hikers that the minimum fine for trespassing on Mt. Isabel is $ 200. Wild boars also reside on the slopes of Mt. Isabel. The views are excellent from the top, stretching south through the Diablo Range, east to the Sierra Nevada (on a clear day), west into Silicon Valley, and north for a close-up of the Lick Observatory on Mt. Hamilton. Climber.org lists Mt. Isabel as an S10 on the Sneak Peak Climbing scale, yet this is way overrated. Mt. Isabel would be about an S4 on the scale.
Getting ThereThe fireroad that leads to the summit of Mt. Isabel begins at the Smith Creek fire station on Mt. Hamilton Road. From I-680 in San Jose, exit Alum Rock Ave. and head east, towards the hills. After about 2 miles, you'll see Mt. Hamilton Road veer off to the right. Take Mt. Ham road for 13 miles, past Grant Ranch County Park, and to the Smith Creek Fire Station. The station is hard to miss. There is no parking at the fire station, yet there are many parking spots along the road only yards away from the station. This is the start of the West Ridge Route.
Red TapeMt. Isabel is on private ranchland. However, this land is so vast that it is unlikely that you'll be caught by any authority figure. To add to that, the road that heads up to the summit of Mount Isabel doesn't look like it has been traveled on (by car, anyway) for a long, long time. Mt. Hamilton Road is subject to closure at Grant Ranch if there has been recent snowfall. Check the CHP road condition site and search for highway 130. The road closure is usually at Grant Ranch Park, in which you must hike through Grant Ranch in order to bag a snow-covered Mt. Isabel.
Sometime between March and June of 2007, the summit log was replaced by a note from the land owner, warning that the minimum fine for trespassing is $200. It is possible that Mt. Isabel might be patroled more in the future, so heads up!
-Thanks to Jared Rader for the new info!
CampingThere are many campsites at Grant Ranch County Park. Click here for info on camping and reservations.
When To ClimbMt. Isabel is best climbed in the fall, winter, and spring. Summer can be brutally hot, and the west ridge route offers almost no shade. The weather on Mt Hamilton, which is only about 1 mile from Mt Isabel, is available here.
Also check out the webcam at Mt. Hamilton. None show Mt. Isabel , but it gives you a look at conditions nearby.