Strenuous: This moderately difficult, 7.6-mile hike will explore the Cerro de Las Posas ridgeline trails with overlooks of Lake San Marcos, the Valley of Discovery and the Pacific Ocean. There will be steep climbs with an elevation gain of 1390 feet.

Meeting location: Ridgeline Trailhead Parking Lot (across from Double Peak School), 102 San Elijo Road, San Marcos 92078.