Profile: uphill from the Saint-Gervais-Le Fayet (altitude: 580.95 m or 1,906 ft 1⁄16 in) to the
col des Montets tunnel (altitude 1,365 m or 4,478 ft 4+3⁄16 in) then downhill to the border (altitude 1,100 m or 3,608 ft 11+1⁄16 in). The steepest grade, between
Servoz and
les Houches is 9% over 2,000 m (6,561 ft 8+3⁄16 in), a record for an
adhesion railway. On the steepest sections (4% and more), it had a central rail for braking (and keeping trains immobile in case of electric
black-outs), through jaws gripping the rail; it was removed around 1980.
Five
Z 800 105-seat EMUs, delivered in 1997 by
ADTranz and
Vevey Technologies in a joint purchase with the Martigny-Châtelard. This 1000
kW stock, composed of two
motor cars, can run at 70 km/h (43.5 mph); it is rack and
pinion equipped, and has
pantographs in addition to 3rd rail equipment, so that it run to Martigny.
Eight
Z 600 EMUs and four additional trailers (some out of service), used in busy periods.
This line carries about 500,000 passengers per year, with wide variation: from 500 people per day in the least busy periods up to 10,000 per day in summer and 2500 per day in winter for the ski season. The customer base is quite diverse, from international travellers connecting with the TGVs, to local transportation, most notably for schoolchildren. It is a tourist line and a public service at the same time.
Through trains between Saint-Gervais and Martigny run under the “Mont-Blanc Express†brand.
Since 2005 travel has been free between Servoz and Vallorcine for those with a
Chamonix residency card and for valley inhabitants.