The best place to pick up the Picton mountain bike trails is probably at the Marina car park. Head up the hill on the Marina to Resevoir Track - it's a well-graded, shared, two-way track. From there keep heading north and you'll pick up the Ridgeline Track - it's about a kilometre long and is succeeded by the Westside Track which runs for another kilometre along the crest of the ridge on the other side of the road. It morphs into the Kanuka track which takes you to the end of the peninsula. It's 3.5 km long and is a benched track that undulates along the side of the ridge. These tracks are all intermediate. They lack technical features but make for a good workout. There are nice views over Queen Charlotte Sound as you go.