how were cable cars/ ropeways built in the Alps? How was all the construction material transported to the top of the mountain?
Really depends on terrain and height and time of construction
Nowdays by helicopters, if it’s not too high..
If there is good roadway, then by cars
Otherwise by mules or other heavy lifting animals (especially in early 19th century)
There are often photos. Like the cables across the grandcanyon. Bridges made by people <often indigenous > carrying long lengths of cable down the south Kaibab or Bright Angel trail.
They just built the building on top and ran the cables.
I saw pics from the same period, early 20th century, of when they built the first metro tunnels and how they demolished buildings, all done by manual labour with picks.
They used carts, pulleys and elbow grease. You’d be amazed to see how they were building bridges in antiquity: https://youtu.be/tggEdsaWbpQ
Most of the time, smaller cables were built at the top to haul materials up the surface of the mountain. These are carried there by hand, and then more and more robust stuff is installed to handle the bigger and bigger stuff
So to start, a hiking team arrives with rope and installs a pulley system. They use that to pull up cables and infrastructure to pull up even heavier loads. If needed, they’ll do that 2-3 times until the final equipment is installed.
They build out the basic lifts first, and then use that to haul up the construction materials to build out the rest of the infrastructure.
Today, a lot of that is replaced with heavy machinery that can mitigate or eliminate the earlier stages. But “man powered” starts are still a super common means of early construction staging.
It’s a lot of work, that’s for sure, but they mostly build those in the summer. There’s no snow, or at least significantly less. Off road trucks with experienced personnel can definitely manage riding up and building on the slopes without the snow with only a bit of planning and a lot of experience.