The John Muir Trail is a spectacular trek through California’s High Sierra from Yosemite (El Capitan and Half-Dome) to Mount Witney, highest peak in the continental US. The 216 mile route can be comfortably fitted into a three-week holiday, but planning and preparation is critical as Ronald Turnbull will tell you – tune in to find out more, then get the Cicerone guidebook and off you go!