Last week I was in Kitzbühel, and took the 3S cablecar to Jochberg. It was terryfing and impressive at the same time. The cablecar spans over 3 km and only has a single support. It flies over the valley below at 400 meters above the ground. I looked up how it was constructed and found a whole channel of cablecar company Doppelmayr where they show some of the incredible things they build.