The 6.3-mile Bonelli Park Loop Trail is proof you don’t have to go far to escape the city. It’s in the heart of the metro area in San Dimas, freeway-close to a gazillion people. But the park’s nearly 2,000 acres of rolling hills give you a sense of distance from the cares of the workday as you circle 250-acre Puddingstone Lake and enjoy views of the towering San Gabriel Mountains just to the north.
You can start the loop trail almost anywhere in the park, but the South Shore Swim Beach is a great choice—it’s right near a park entrance, and there’s plenty of parking and restrooms available. The trail starts at a bridge just to the right of the parking area and leads you counterclockwise around the lake. Along the way you’ll intersect with several roads, but just keep the lake on your left, and whenever you reach a fork, stay left. The trail passes over hills covered in wild mustard and under the shade of coast live oak trees before crossing through the Puddingstone RV Park. It then follows a creek through a shaded area leading to a wash and eventually dead-ends at a picnic area—a nice place to grab a trail snack.
Continue making a counterclockwise loop, and pay attention when the trail zigs and zags back and forth across Lakeside Drive. Evening hike bonus: Lots of desert cottontails and waterfowl are out and about, plus sunset views over the lake. If you’ve worked up a sweat (hope so!), you can take a post-hike dip at the swim beach till 6 p.m.
Bonelli Regional Park is just off the 57 Freeway in San Dimas between the 10 and the 210. Exit onto Via Verde toward Raging Waters Dr. and turn left on Via Verde. Turn left into the park and follow signs for the South Shore Swim Beach. The park is open sunrise to 9 p.m. April through September and sunrise to 7 p.m. October through March. Dog-friendly!