The #MontBlancExpress leaves the🇨🇭Rhône valley just north of #Martigny: the steepest gradients require the use of the cogwheel and, in particular in tunnels, the 850 V DC are being collected from a third rail rather than from a catenary, thus reducing the loading gauge. At Vallorcine 🇫🇷 we change to a French #SNCF #TER train (yet there are also some through services, running over the entire line). 2/4