East of San Diego and El Cajon, the 18 mile Nobel Canyon loop is arguably the premier mountain bike ride in the area and offers some of the most beautiful scenery around. On the western slopes of the Laguna Mountains, the route passes through light pine and oak forest, and combines rocky singletrack with fire roads for a total vertical of almost 2000. This is a challenging, rocky trail acending scrub brush covered mountains.
To reach the mountain biking trailhead from San Diego, head east on US8 past El Cajon and Alpine (about 43 miles east of San Diego). Exit at Pine Valley and head into town. Turn left on Old Highway 80 for about a mile to Pine Creek Road. Turn right heading northeast on Pine Creek Road for about 1.5 miles to the Noble Canyon trailhead.
The trail heads out from the parking area. Many people continue heading up Pine Creek Road to old Deer Park Road to Indian Potrero Road for a total of 9 miles, and then head back down via the Noble Canyon Trail (see map).
Overall, Noble Canyon Loop is the 5th most popular mountain bike trail of all 132 mountain biking rides in California.