Two lengths of parallel banking were observed on the north-west-facing slope of Black Mountain, above Pencaegarw Isaf.
They follow a roughly east-west orientation crossing steep stony ground and consist of stone and boulder banks overgrown with grass, bracken, bilberry and moss.
The lower of the two is a stony scarp 1m-1.5m wide at its west end spreading to 3m wide at its east end with a height of no more than 0.4m. It can be followed for a distance of 110m.
The upper bank is similar in character to the lower one though is better defined and begins a little further to the east. It follows an irregular path for 120m, averages 3m wide and 0.4m high.
The purpose of the banks is unclear. Though they appear to form the eastern extension of a system to the west the ground between these two banks is too steep and stony for cultivation.
The banks are associated with two small ring bank structures probably hut circles.
