We finished the second visit with the classic 5C via ferrata to summit of Monte Agner 2872m.
With a Cicerone guide we were able to get a taster on the lowest grade 1A then progress at a comfortable pace to 3C by the end of 2 weeks. We did a 4A during this time but felt we'd pushed it a bit (having jumped straight from grade 2, missing out grade 3). The numbers represent technical difficulty and the letters the overall seriousness (or remote rating). 3C's were good fun because they were straight-forward rechnically but took you into more isolated terrain. 5C felt like Dif to V Diff climbing, though sometimes with an amount of exposure, which you do get used to. As a back up on the harder grades, I carried 30m of 10mm rope and a couple of long slings and krabs so that I could quickly set up a belay/lowering/abseil system using the existing fixed equipment. Generally with the C grades you need plenty of stamnina to get back down the mountain after finishing the ferrata.
The routes can mostly be done in fell or approach shoes but some necessitate glacier crossing and maybe boots/axe/crampons. You should carry a minimum of 1.5 litres of water each per day, any less and we found headaches and poor perfomance an issue.
