Ran at Chino Hills State park today. Its a large, nice park with lots of trails, multiple entrances and is split between Riverside, Orange, and San Bernardino counties. We started out from the Yorba Linda side at the Fairmont trailhead. Started down Easy Street to Telegraph Canyon, then up North Ridge trail (which is all uphill). Reached Gilman Peak (2,000ft elevation gain from start), then headed down Sycamore trail (single track) to Telegraph Canyon and back up Easy Street to the trailhead. Total distance 10.7 miles. Details here.