I live in Medford and the main 4x4 areas are really forest roads with old skid trails to play on. We also have an old wagon trail (45 minutes away) that is open starting in late spring (Mcgrew Trail). The area west of Ashland has a lot of old roads and trails but nothing really used a lot. There is an area up Evans Creek that follows the powerlines and is called Elderberry Flats and it is a campground. Jackson County Sports Park has some mud pits and 4x4 obstacles set up, works great for teaching and testing. Then you can always head over to the coast and play in the dunes. 2.5 hours will get you to the dunes, and also to the Bend area which has the Edison Trail which is also a seasonal trail.
Hope this gives you some info. Bend 4x4 club is Home
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