Backpack the Pacific Crest Trail
The 37-mile-long segment of the PCT through Cleveland's Descanso District is well worth a long-weekend trip in the cooler months. It goes through chaparral in the lower elevations, but riparian-oak woodlands are encountered on the climb toward the recreation area from the south. The trail can be entered at several locations; many people enjoy hiking short distances (two to ten miles) of the trail. At the upper elevations, hikers and riders will enjoy the pines and oaks lacing the trail.

Bike the San Juan Trail
This fat-tire ride runs 12 miles in the Trabuco ranger district. It's a great introduction to the Santa Ana Mountains, featuring some truly unique flora - deep red monkeyflowers, purple nightshade, and tall, spiky yuccas with silky white flowers. Lizards dart here and there among the foliage in this dry but thriving area. Ancient oaks provide you with shade from the hot sun.

Drive Sunrise National Scenic Byway
Drive through the forest. Along route S1 you'll see mountain meadows and forest, as well as spectacular views of Pine Valley and the Anza-Borreqo Desert 6,000 feet below. The 24-mile drive takes about one hour.

Hike the Observatory Trail
The five-mile ascent to the Palomar Observatory is a lot of fun. You'll find the trail a well-graded aerobic uphill climb, but there's only a 600-foot elevation gain. The shade is dense from oaks and pines, and giant pinecones fall along the trail. A half-mile up you'll reach an overlook platform from where you can gaze at the lovely Mendenhall Valley. The trail ends at the observatory, where you can see the Hale telescope. Hike up a couple flights of stairs to the telescope viewing area and learn all about it. More than 100 billion galaxies are within spotting range of the Hale telescope.