do yourself a favor and do the Downieville Downhill. I'd rate in in the top three best MTB rides I've ever done, right up there with The Whole Enchilada and Captain Ahab in Moab. Imagine flying through an old lime green moss covered ponderosa pine forest at warp speeds. Ever see Return of the Jedi where they are flying through the Endor forest on speeder bikes? It's 17 miles of that. Oh, and there are some technical bits too. I rode down a feature that is a literal waterfall (a gradual slope, not a straight drop) with water flowing through it that's part of the trail. The only caveat. Gas up first. There are no working gas stations within 20 miles of the town of Downieville. Also, there's an excellent pizza place in town.