A bone assemblage of 133 bones from a series of upland environments in central Wales is described. The study area comprises unfenced hill land on the tops and upper slopes of the hills that is interspersed with fenced rough grazing in the valleys between. The area is largely grazed by sheep with some hill ponies and occasional cows. Wild animals include foxes and badgers in addition to small mammals. The bones are a surface assemblage from natural deaths of sheep, and this assemblage is linked with a long term taphonomic naturalistic experiment based on over 100 individual animal carcasses continuously monitored since time of death. Preservation of skeletal elements is found to be strongly associated with structural density of the bone, with more dense bones being preferentially preserved. The bones have been dispersed by the scavenging activities of foxes and dogs, and in the process some elements have been broken, producing a characteristic spectrum of gnawing marks on the surfaces of shafts, articular ends and on the edges of spiral breaks. Bones have been subsequently modified by weathering and transport, resulting in significant loss of material. The resulting bone assemblage is described together with the modifications produced by the above-mentioned taphonomic agents.