"This loop, which includes all or parts of the Diablo View, Spengler, Old Briones Road, Pine Tree, Orchard, and Alhambra Creek trails, gives you a chance to explore the East Bay’s largest developed regional park, an area of deep wooded canyons, forested slopes, oak savannas, and open, grassy ridges. The varied habitat attracts a large variety of birds, from chickadees to golden eagles. The plant life along this route is equally diverse, with a wide range of trees, shrubs, and wildflowers. From the southeast corner of the parking area, pass through a gate next to an information board, turn immediately left onto the Diablo View Trail, a dirt road, and follow it gently uphill. Another dirt road, heading straight from the gate, is the Alhambra Creek Trail, part of your return route. This is open, rolling country, the realm of grassland and oak savanna. Soon after leaving the parking area, you pass the Tavan Trail, left, and now the slope changes to moderate as you ascend via well-graded S-bends toward the top of a ridge, where a fine view of Mt. Diablo awaits. Along the way, you pass the Hidden Pond Trail, left, a dirt road. From the ridgetop you also can see Concord, Highway 4, and the west delta."