I usually do my best to avoid tunnels, but I was a little tired from the climbing earlier, and decided to take the fastest route down. . I rode in the road, without much of a bike path, but nothing scary. there is a very narrow walkway if you wanted to give that a shot, but it was too narrow for me. I went through on a holiday around 3:00 and there was very little traffic. I made it down to Iga very quickly! I'm pretty sure I would not have enjoyed riding up the hill in the tunnel, the old road was empty and a lovely (if tiring )ride through the woods on the way up.