Why not just drive down I-5 to say, Medford, OR and cut over?
You would think this is the fastest route. I-5 is the biggest road heading south. However, there is lots of commuter traffic between Vancouver, WA and Eugene, OR which can slow you down. There are also lots of passes south of Eugene and the route takes you really far out of the way. I-5 has the highest posted speed limit, but it’s only 5 MPH higher than traveling on US-97.
