If you ever find yourself in San Francisco with a bike and the weather is clear, you cannot miss this ride. You head over the GG bridge where all of the usual routes start, but instead of heading down the hill towards Sausalito after the car park, take the road up to your left. It climbs up pretty steeply to the viewing area at the top, but if you hit the time just right, the view is amazing. When you get up there go right to the back of the car park where the two lane road ends and you will see a barrier that is the start of a single lane road and decent towards the Marin Headlands. This is a fast and twisting descent, where it is hard to know if you should keep your eyes on the road or the Pacific. Once on the Headlands there are endless roads to build your ride from and you can come back through the 5 minute tunnel on the bike lane, that will drop you right back at the bridge. San Francisco you are spoiled to have this on your doorstep.