Regarding the tunnels , Do u think its possible to run a train without airconditioning inside that ? if we run then ppl ll suffer asphyxiation due to lack of oxygen. Just for the 5km tunnel near Karwar , i have heard many people saying they have pain in ears due to the pressure difference. For 50-60 Kms we need long tunnel we need to run only AC trains with AC cabs for drivers. By the way train in switzerland run in hills but here it climbs from a coastal plain to plateau , there is a difference between the both . Climbing a plateau within a short distance is not an easy task. There trains run at 250 Kmph , here it will 45kmph for the trains which ascends and 30kmph for the trains which descends, so it needs more than 1.5 hours.