San Juan Trail is one of the gems of South Orange County. Located off of the 74 / Ortega Highway. The trail is known for its long sustained climbing, sections that require technical skills, long descending, and gratuitous amounts of single track in both up and down directions.
Ours was a classic loop; up to Cocktail Rock, then on to Blue Jay Campground, and back down to Cocktail Rock before starting the long descent back down to to the parking lot. The best part about this loop is how far you are from everything - there seems to be no signs of civilization or cell coverage until the Blue Jay Campground. For that reason, be sure to back food, water, and tools.