Mud got a flat 10 miles before the end. We were climbing Trinity Road. I kept going. Once at the summit, it was really close to the end, so I still kept going. When I got to the car, I realized that I did not have the key. I stretched, stretched, and stretched. At that point, I knew Mud must have made a wrong turn. I wasn't worried because we still had plenty of day light. There was very light traffic in the area, although the roads were not completed deserted either. He would make it back one way or another. So, I took a pleasant nap in a quiet alley way near our car like a homeless person.
We each had a hand-written (by me) note like this one below for directions. It was clear to me: L for left, R for right, and arrow for continue on. He mistook the arrow for a right turn and did not look back to check the road signs, so where he should have continued on Oakville Grade, he made a right on Dry Creek Rd. It kept going until it deadended somewhere in Napa. Oops.
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Each of us did the ride on one water bottle. I guess it was harder on Mud since his ride was almost 20 miles longer.