We joined 101 south from state hwy 18 after a Portland stay. 101 varies anywhere from a full on freeway to the legal narrowest of two lane state highways through several redwood sections with 25-30 mph signed curves. How narrow is it? The overspray from the white line on the side of the road is seen on the base of some trees. The road was built around the trees like a slolom course. We are 36ft plus toad which makes meeting logging trucks and 18 wheelers in these sections a little tight but OK as long as you stay between the lines.