This is the Harter Fell I always refer to as 'the other Harter Fell', not because I think the Eskdale one is superior, but for no other reason that I walked on the Eskdale one first.
This is a fell with two totally contrasting faces, the southern side of the fell is grassy, gentle and to an extent, somewhere you could happily wander about and explore with ease. The northern side however, has an impressive collection of rocks, scree and boulders and if I were to stick my neck out, I'd go so far as to say from Haweswater, Harter Fell is just as impressive as anything you'll find in Wasdale or above Glenridding.
If you approach the summit from Gatesgarth Pass or Kentmere Pike during poor visibility, the fence helps to ensure you don't miss your target. The difficulty here would be walking to or from Nan Bield Pass. Given the amount of rocks and crags in the area, you don't want to get this wrong.