The Jackson Lake Trail is a high-quality singletrack snaking through the woods on the northern slope of the San Gabriel Mountains. Some of the most beautiful forest in the range can be seen along the trail, including huge ponderosa pine, jeffrey pine, white fir, live oak, black oak, big-leaf maple, alder, and willow. The black oak and big-leaf maple turn brilliant reds and yellows in the fall, providing a photographers' feast that includes tremendous views across the southwestern Mojave Desert.
Easy access and loop options make for a nice part- or half-day ride. Combining this trail with other nearby trails and roads, a full day of excellent riding can be had. Adding a 'panhandle' to the shortest loop option by climbing to the top of West Blue Ridge provides stunning views down the East Fork San Gabriel River and across to 10,064' Mount Baldy (aka Mount San Antonio). Also, a visit to the Grassy Hollow Visitor Center can be made, where nature exhibits can be viewed and information, maps, and water obtained.
This trail is most commonly ridden in the downhill direction, travelling from west to east. That is how the description here will be oriented, though riding the opposite direction makes for a pleasant climb.
The trail starts at a junction of the Pinyon Ridge Truck Trail and NF Road 3N26C. There is a hairpin turn in 3N26C just past the Pinyon Ridge 'Y' intersection, if travelling from Vincent Gap. On the outside (left) of this curve, the trail branches off into an open forest of jeffrey and ponderosa pine. Smooth, buff trail zips through this section, with meadowy slopes shaded with pines.
The trail narrows after a while, and gets a bit rocky. A couple short climbs are encountered as the forest turns to shadier white fir. After cutting across several small gullies, the trail crosses the upper part of Pinyon Ridge, at a huge dead ponderosa pine. There is a faint trail leading down the ridge, but not recommended for bikes.
The terrain gradually becomes more interesting, with traverses across cliffs and some dry and rocky creekbed crossings. The views of the Mojave Desert open up in this section, giving a dramatic backdrop to the scene. Some narrow sections are encountered, where the soil is loose and ready to slide.
Then the trail mellows and begins a long traverse toward its lower terminus. There are a few more tricky rock gardens, but the remainder is mostly just fast, buff trail through the woods. This lower section of the trail passes through groves of black oak, which turn brilliant red in autumn, don't forget the camera! At the end of the trail, go left and follow the dirt road, making a right at the next split, and continue down to the parking area near Hwy N-4.
If approaching from the west (greater Los Angeles, Ventura County, etc), directions begin at Hwys I-5 / CA-14 junction. Follow CA-14 north and east to CA-138 (Pearblossom Highway) and exit, continuing east on CA-138 through Little Rock and Pearblossom to Largo Vista Rd. Go right, heading south toward the mountains. At N-4 (Big Pines Highway), go left (east) and continue up to Mountain Oak Campground (approx. 1/4 mile before Jackson Lake) and go right onto a dirt road. Veer left as the road splits, and continue a short ways to a parking area.
If approaching from Ridgecrest / Inyokern, follow Hwy US-395 south to Bear Valley Cutoff, then go left (west) and continue to CA-138. Go right and continue to Largo Vista Rd.
If approaching from south and east (San Bernardino, Riverside, San Diego, etc) follow I-15 north to CA-2 and exit. Go left (northwest) and continue on CA-2 through Wrightwood to N-4 and make a right. Follow N-4 to Mountain Oak Campground, 1/4 mile past Jackson Lake, and go left on the dirt road to the parking area.
When to BikeSpring, summer, and autumn are best. Winter brings heavy snow, so the trail is usually covered. Occasionally a dry winter will leave the trail exposed, but it can be cold at this elevation.
Loops and Options
As well as riding this trail as a loop ride, usually via the Pinyon Ridge Truck Trail, there are also side trips of interest, and enchainments with other big trails of the area.
Loop Using Pinyon Ridge Truck Trail
From the parking area at the lower end of the trail, near Jackson Lake, ride back toward Hwy N-4. Just before reaching the highway, the dirt road veers left and descends through a summer camp. Just past the camp is a familiar Forest Service locked gate. This is the start of the Pinyon Ridge Truck Trail. Mellow climbing is encountered as the road heads west. At a saddle overlooking Camp Fenner the Pinyon Ridge Road branches to the right (northwest) and climbs to the top of Pinyon Ridge. This is a fair side trip with excellent views and a nice pinyon forest. The Truck Trail bends south from this junction, and the climbing gets steeper for the last couple miles to the trail.
Loop Using N-4, CA-2, and 3N26C
From the parking area, return to Hwy N-4 and go right. Ride past Jackson Lake and climb steeply up to CA-2. Go right and make a steady climb up to Inspiration Point, continuing to Grassy Hollow and the start of 3N26C. Go right and pass through the Grassy Hollow Picnic Area, where water is available, and a visitors center has exhibits. Go around a locked gate and continue up and past Jackson Flat Group Camp, then descend past another gate, cross the Pacific Crest Trail (closed to bikes!) and drop down to the trail.
If riding the Pinyon Ridge Truck Trail variant, it is worth the extra effort to continue past the trail on the way up and ride 3N26C up to Jackson Flat Group Camp. It's an excellent place to rest (if not in use) and has an observation deck built on top of a water tank. This is an excellent viewpoint overlooking the whole drainage of the East Fork San Gabriel River, with 9399' Mount Baden-Powell on the right, and 10,064' Mount Baldy on the left framing the scene.
An excellent full-day ride, for those abusive of self and gear, can be had by combining the Jackson Lake Trail with the Blue Ridge Trail, several miles to the east. The Blue Ridge Trail is another high-quality singletrack, equally scenic, but much shorter at 2.5 miles. Ride up the Pinyon Ridge Truck Track, then 3N26C, and continue to CA-2. Go left (east) and on to the East Blue Ridge Road at Inspiration Point. Go right and continue east, flat at first, then climbing up and into Mountain High ski area. About 1/2 mile past Mountain High West the road enters Blue Ridge Campground. On the other (eastern) side of the campground, where the lower end of a ski lift is, the trail goes left (north) and dives down the mountain. From the bottom of the Blue Ridge Trail, at the N-4 / CA-2 junction, go left and climb CA-2 back to Grassy Hollow and go right on 3N26C and return to the Jackson Lake Trail and follow to the other end.
Double Whammy Extra Credit
When combining the Jackson Lake and Blue Ridge Trails, I like to add on a trip to the very top of East Blue Ridge, at 8400' elevation. If one is so inclined, continuing east along Blue Ridge is also worth the effort, as I have often spotted bighorn sheep in this area. Also further east on Blue Ridge is the upper terminus of the Acorn Trail leading into Wrightwood.