I recommend that you bring a ligh as it can be extremely dark inside the tunnels. The trail goes all the way to Truckee, but if you do that I recommend that you leave a car there, because of all of the elevation you lost on the way down.
Heading on eastbound I-80 exit at \"Soda Springs Norden\" and take a right on Donner Pass Rd. Continue past the flashing red light to the road going to the Judah side of Surgarbowl, there is a surgarbowl sign on the corner. Immediately takea right and you will see a tunnel go under the road. Thats the begining of the ride.
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