Lead-climbing is also discouraged for reasons of conservation - it is unacceptable for climbers to risk further damage to the thin rock crust on the surface of the crags. Unconsolidated and friable sand lies beneath this crust. Deep rope-grooves can be seen in places at Harrison's Rocks and are testament to the fragility of the rock.
Climbing with lead ropes is discouraged because of environmental concerns - it is unacceptable for climbers to risk exacerbating damage to the delicate surface rock on the crags. Loose and erodible sand lies beneath this crust. Visible rope-grooves at Harrison's Rocks demonstrate the fragility of the rock.