I was hiking over Donner Pass yesterday and came across the bronze plaque commemorating the Summit Tunnel project. I looked around in all directions and wondered why the engineers decided to tunnel through so much rock when there appeared to be an alternative. The alternative, to me, seemed to be to add a few extra loops to the route to gain the needed elevation to cross the summit without the need for a tunnel. Would you direct me to the appropriate link which explains why the engineers chose to spend so much time, money, and material to save 125 feet in elevation?
—Ed Hodges, San Jose