Hiked beyond the end of this road. The end is the far end of the 2nd tunnel. Be aware that there is a commercial beehive along the way, but the bees don't usually bother you. But there is a wild hive in the 2nd tunnel, and we got a couple of stings. We tried to hike beyond the 2nd tunnel, but after about 1/4 mile the going gets really rough, and then the path disappears altogether.
On the way back, we encountered a rattlesnake on the side of the road, so keep your eyes open. I think going early in the morning would have minimized both of these hazards (bees and snakes). I still really like this place, though!