Categories Uncategorized Stonyvale Picnic Site Post author By traveloutside.admin Post date May 7, 2020 Picnic Site. Day use hours are 6 am to 10 pm. Directions GPS Coordinates Latitude 34° 17′ 5.7552″ N Longitude 118° 13′ 25.0356″ W ← Mill Creek Summit Picnic Area → Vogel Flat Picnic Site