Choppers are widely used to carry up stone for paths on hills throughout the UK. Over here on the east coast there was a chopper delivering rock into the path along Maybecks near Whitby for just over one day. It made a lot of trips. I remember several years ago a stone stairway was constructed up the sides of Jugger Howe beck on the Lyke Wake Walk and the chopper (with or without the stone load) cost £90.000 to deliver it.
The path from 9 Standards to Keld is more like a swamp even in good weather
Nice photos by the way. Hope it didn’t spoil your activation.