Gower Truck Trail is located near Ramona, CA. The trail is primarily used for hiking.
Head out from San Diego Country Estates toward Eagle Peak Rd, then down to the river - wonderful area to explore, and a very, very rugged way to approach Dye Canyon when the water is low. Stick to the trail, as some of the heavy brush hides very steep terrain underneath. Years ago, I used to hike out the road, down the canyon wall, then along the river back to the Gower Truck Trail to make a loop - not sure if those trails are still serviceable.