As before, I was able to rent a really good bike for a remarkably low price. This time I was offered a Marin Stelvio Di2, with carbon frame and electronic shifters, for a very reasonable $38 (£25) for 24 hours. (By way of comparison, Station Cycles in Cambridge charges £35/day for a ho-hum aluminium road bike)
My previous two rides from here had started at the bike shop and taken me west into the Santa Cruz mountains, which offer superb cycling country with quiet roads, lovely scenery and challenging climbs. This time, however, I fancied doing something different. So after handing over my credit card and receiving the bike I bundled it into the back of my rental car and drove north towards San Francisco, over the Golden Gate Bridge and into Marin County.
My plan today was to spend half a day on a ride to the top of Mount Tamalpais. This is the highest peak in the Marin Hills, about 20 miles north of San Francisco. I was tempted by an article I found online which described the ascent of this mountain as being a Bucket List ride if there ever was one.
The ride started in the small town of Fairfax, one of a series of pretty and very well-todo towns in Marin County. The moment I arrived it was clear that this was a popular base for bike rides: the Marin Museum of Cycling is here, and I saw dozens of sports cyclists riding around. I parked the car, got on the bike and set off south-west along Bolinas Road towards Mount Tamalpais. It was about 2pm, which would give me just enough time for a 37 mile loop to the summit and back before sunset at 6.15pm.
The road started to climb almost immediately, but it didn't take me long to work out how to use the electronic gear shifters and I settled into a comfortable low gear for the long climb into the Mount Tamalpais State Park. As I rode along I encountered several cyclists speeding down the hill in the opposite direction, and was overtaken by one or two going the same way as me.
Today was 31st October but it was hot in the afternoon sunshine. I hadn't brought sunscreen so was relieved to discover that I was soon riding in the shade of redwood trees.
The road wasn't particularly steep and my lowest gear allowed me to climb fairly easily from about 50m in Fairfax to over 300m before descending 100m or so down to Alpine Lake, a reservoir on the Lagunitas Creek. Rather to my surprise the road surface was quite poor, with numerous bumps and patches making it necessary to take care on the downhill sections.
I crossed Alpine Dam and began a long climb up to the ridge. Once again the gradient was not especially steep and I was happy to take my time, winching myself up in my lowest gear. I wasn't the slowest climber, but inevitably I found myself overtaken by one or two others on the way up.
After a while the trees came to an end and I found myself riding along an exposed ridge, with the Pacific Ocean below me on my right.
This was probably the most enjoyable section of the journey to the top, with fine views and an undulating gradient that allowed me to try out some of my higher gears for the first time.
After a while I reached a tee-junction and turned left for the final few miles of ascent to the summit. Once again this was easier than I had expected, and it wasn't long before I spotted the spherical radar domes of the West Summit.
The view from the top was astonishing, with a huge vista of the San Francisco bay before me and the towers of San Francisco clearly visible below. My immediate reaction was to wonder why I had never been here before: I've visited San Francisco about ten times now but I've never seen a view like this.
I continued on for a couple more miles to the east summit, where the road ended. I wasn't the only cyclist catching the breath and admiring the view, so it was easy to find someone to take my photo.
To reach the actual summit I had to park the bike (fortunately I had been loaned a lock) and walk along a rather rough rocky path for about ten minutes to the top.
After about twenty minutes or so at the summit it was time to begin my descent. It was now 4.20pm, two hours from sunset, and I still had 20 miles to go. Naturally the journey back down was much faster than the journey up, and I enjoyed an exhilarating ten mile descent along smooth roads down to the town of Mill Valley.
The final leg of the ride took me through a series of Marin County towns: Mill Valley, Corte Madiera, Larkspur, Ross and San Anselmo. This section was much more urban than before, and there were numerous reminders that it was Halloween. In the town of Ross I found myself riding along a residential street which had been closed to motor traffic and taken over by trick-or-treaters dressed in elaborate costumes.
This section of the ride was the busiest in term of motor traffic, but it was still very quiet by Cambridge standards, and the busier roads had reasonably good cycle lanes.
I arrived back at Fairfax at about 6.10pm, just before sunset, and having cycled 38 miles.
Download GPS track (GPX).