These are heavenly trails for mountain bikers, along with dirtbikes. There are extreme climbs, deep dark forest, 11 inch wide snake trails, and snow trails. Bring plenty of water and a friend. Dirtbikes must use spark arresters, and watch out for the bikers. traffic is actually very light. I saw one pair of bikers, and two dirtbikes all day.
How to get there:
From Redding, take 299w. Go down about 5 miles or so, and turn right at French Gulch. Go down another 3 or so miles, and turn left on French Gulch road. Go to the end, and you come to the trailhead. Have fun