I went up with a local and we were stopped by a Ranger on our way up after dark. He was insistant that we went no further but did NOT say it was illegal for us to continue. He just warned us that if anything were to happen the Rangers would not be there to help. We went to the top and had a wonderful view of the stars. I got a bit quesy from the altitude but the rest of my party was fine. We were in a 4wd truck. I wouldn't reccommend it in a 2 WD auto the dirt road was a very rough one.