Kwaay Paay Peak Trailhead in San Carlos launches one of San Diego's steepest summit hikes inside Mission Trails Regional Park. The out-and-back route covers roughly 2.4 miles with 882 feet of elevation gain, climbing from 299 feet at the parking area off Father Junipero Serra Trail to a 1,194-foot summit that ranks fourth-highest in the park. Terrain shifts from sandy chaparral and manzanita thickets on the lower switchbacks to a staircase of exposed granite in the final quarter-mile push, where the grade tops 15 percent and the trail narrows to single-track. The same steep-grade conditioning that attracts distance runners preparing for longer mountain races draws indoor climbers from Grotto Climbing & Yoga in Grantville, where bouldering and top-rope sessions build the grip strength this trail demands. The summit stone marker sits at the geographic midpoint of the park's 5-Peak Challenge, a program launched in 2015 that logged more than 15,000 completions before closing in 2020 and still draws trail runners stitching all five summits into a single 16-mile day. Clear-day panoramas from the top sweep from downtown and Point Loma to the west through Mission Gorge and the San Diego River valley below, with North Fortuna and South Fortuna rising across the canyon to the north. Spring wildflower season brings California poppies, foothill penstemon, and buckwheat blooms along the ridgeline, and birders log Cooper's hawks and Anna's hummingbirds through the chaparral belt. Parking is free at the Father Junipero Serra Trail lot across from the trailhead, which shares access with Old Mission Dam Historic Site less than half a mile south. Leashed dogs are permitted on the trail, though bikes are not. Post-hike refueling in the 92119 ZIP runs through the Lake Murray Boulevard corridor, where Cowles Mountain Coffee pours espresso and cold brew built for the Cowles Mountain and Kwaay Paay crowd. The trailhead sits roughly four miles northeast of SDSU, accessed from Mission Gorge Road to Father Junipero Serra Trail. Most hikers budget 90 minutes to two hours for the round trip, though runners regularly cut that to under an hour on the descent.