Henninger Flats Professional Review and Guide
"Park-like Henninger Flats is a pleasant surprise to come upon after the sunny, often sweaty climb up the lower end of Mount Wilson Toll Road. The flats and slopes hereabouts have been the site of an experimental forest for more than 80 years now, with seedlings of pine, cypress, cedar, and other trees raised for reforestation projects.
Run by the LA County Fire Department, the area encompasses four delightful camp and picnic areas, a visitor center, a pioneer museum, a short nature trail, and a seedling nursery. Backpackers register with the ranger on duty. Campfire permits and wood are usually available."