The old, paved rd, OR Mtn Rd, Hwy 324, over the mtn is still in decent shape, about 6 miles long. S of the tunnel, it's on the W side of 199. N, on the East side. I put my flashers on, & for the down hill half, geared down my Corolla. No problems, i.e., w/ ground clearance.
At the rest area, there's a gated, abandoned rd that can be walked/biked, to the 324. Caltrans' rules include, no such hikes, while parked there. Fortunatly, there's a turnout, SW of the Rest Area.
Neither rd has dramatic views, but goes thru lush, temperate rain forest; quite nice. Plenty of camping spots, along the 324. At mile post 3.29 is a 100 yard spur, w/ a turn around. Opposite that, & 70 yds downhill on the 324, is where the Rest Area rd intersects, blocked & disguised by a dirt mound.
The tunnel height is 15 feet, 1 inch according to the sign mounted at the entrance.
Enlarge the photos and look at the clearance sign. Have a good trip.
I would helpful to know the maximum height for vehicles passing through the tunnel. I'm from out of state and always concened if my 5th wheel will have an issue on bridges and tunnels. Thanks Paul