South Ridge - Crystal Lake Trail

South Ridge - Crystal Lake Trail

Page Type Page Type: Route
Location Lat/Lon: 34.31891°N / 117.84471°W
Additional Information Route Type: Hiking, Mountaineering, Skiing
Seasons Season: Spring, Summer, Fall, Winter
Additional Information Time Required: Most of a day
Additional Information Difficulty: Walk-up
Sign the Climber's Log


This is a simple, if currently inconvenient trailhead to access. It offers the steepest, longest route to the summit of Mt Islip, and gives good views towards Twin Peaks, Williamson, and Waterman.

Currently, Route 39 (Azusa Avenue) is closed just a few miles north of the Azusa Canyon Off Highway Vehicle Area due to the fires in the area, which destroyed multiple homes, and most of the foliage on Islip's eastern face.

[img:251545:aligncenter:medium:Looking down into Bear Creek]

Folks who ride bikes for sport (on road) might find this route appealing, as the 11 or so mile section of closed R39 road to the trailhead is in nearly perfect condition, and is popular amongst local cyclists. One could combine the ride up and back down with an ascent of Mt Islip, and perhaps South Hawkins, Sadie Hawkins, Middle Hawkins, and Mount Hawkins, if they have the energy.

Update: As of June 2007, R39 is closed at "Valley of the Moon", 3.25 miles north of the previous closure.

Getting There

From 60/10/210 freeways:

Best way is to exit the 210, exit AZUSA (R39), head north. Stick to Azusa Avenue through the canyons where it becomes San Gabriel Canyon Road, until it dead ends at a large orange gate. The location of the locked gate changes sometimes mutliple times per year, completely dependant upon road conditions, politics, money, and weather. As of Summer 2007, it is closed at "Valley of the Moon", mile marker 32.12, just south of Coldbrook Campground.

[img:362444:aligncenter:medium:The ridge in profile, descending left/south]

The trail begins just east of Crystal Lake, which lies in the eastern portion of the "bowl" formed by Mt Islip and the various Mt Hawkins peaks. The trailhead is located at the southwest corner of the small Crystal Lake parking lot. This is the smaller, southern of the two parking lots. If all else fails, you can go directly to Crystal Lake. At the southern end of the lake, move into the obvious saddle. You should very easily be able to pick up the well-mantained trail and head west and north to Mt Islip.

Please look at the coordinates for more exact information.

Route Description

The route is a simple walk-up, starting at Islip's ridge in the south, and heading directly north to the summit. From the summit, one can either retrace their steps, or bail to the east down the obvious ridgeline towards Little Jimmy trail. From Windy Gap, you would be forced to wind your way south through the roads in the bowl to gain acess to R39.

[img:362445:aligncenter:medium:Old-growth areas have deeper snow]

If the trail is obscured in winter, simply head north along the ridgeline to the summit. This adds some class 2 sections, but you should not find anything more difficult than this.

This trail is not especially steep, and I feel it would make for great cross country skiing. A quick method of leaving the summit would be to possibly ski down the southeast face of Mt Islip, which is rather open, and not especially steep.

Essential Gear

Bring plenty of water. Crystal Lake is a good source for filling up if you have a filter or a purification system.

An ice axe and crampons are suggested in the winter, as snow levels will drop below the 8,000ft+ summit of this peak. Snowshoes may or may not be a helpful addition in high-snow years.

Additions and CorrectionsPost an Addition or Correction

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StartingOver - Jan 13, 2016 12:17 pm - Hasn't voted

State Highway 39 now open all the way to trailhead

State highway 39 is now open all the way to the trailhead about 0.5 miles past the Crystal Lake cafe. The trail to the summit of Mt. Islip is about 3.5 miles long with about 2,200 feet of elevation gain.

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