We wanted to go through the park and had only seen the valley at bottom and top. I recall going past Sacramento and on approach to Tahoe were signs on the road from the night before yet to be turned around that only vehicles with chains were permitted. Must have been over 30 years ago. We had driven around from visiting brother in law in Orange county in September when it was 105 degrees. Years before we had driven from brother in laws to Las Vegas. Huge areas compared to little Delaware where I used to cycle a 60 mile loop through DE, MD and PA. Think PA and CA have about same population densities and there are sparsely populated regions of PA.