For some good gravel/dirt riding with a lot of climbing, butler creek is a good place to check out. While most people think of snowbowl as being up Grant creek, it is actually in the Butler creek drainage, which is the next one over. From Grant Creek, when you turn onto snowbowl road, you climb over a saddle into butler. Snowbowl road climbs the east side of butler creek and ends at the ski area. There is also a road on the other side from Butler creek, and you can make a loop out of the two on a bike. On top of that, you can ride to the top of tv mountain, snowbowl, and point 6 on actual road, and there's some singletrack down the front of the ski hill.
Getting to snowbowl via snowbowl road is pretty straightforward, so I don't think I need to go into much detail. But if you've never been in butler creek it's nice to have a map or gpx track to follow, as there are a couple of junctions up there. The main thing to keep in mind is that you actually want to take Point 6 road when you get there, as that is the actual name of the road that continues to the top of Butler creek (and all the way to Point 6).
The most basic route is to climb to the base of snowbowl via one of the roads, and descend the other
