I took this photo last month, from the train up the beautiful Puster valley from Fortezza to San Candido in the South Tirol.
The vehicles are heading in the opposite direction, out of Austria towards Italy. They are creeping along. Narrow valleys are a curse for cars, they force everyone onto the same road where they get in each other’s way. They are a blessing for public transport: the routes on which people want to travel are less diverse (basically, just up and down the valley), which makes it easier for “mass transport” to meet their needs economically.
Result: energy efficient passenger transport is easier to arrange in the mountains than in equivalently rural areas down on the plain.