 With the exception of the Neolithic settlement at Cefn Glas , there are three certain pre @-@ Medieval settlement sites in the valley — Maendy Camp , Hen Dre 'r Gelli and Hen Dre 'r Mynydd . The earliest of these structures is Maendy Camp , a hillfort whose remains are situated between Ton Pentre and Cwmparc . Although its defences would have been slight , the camp made good use of the natural slopes and rock outcrops to its north @-@ east face . Maendy camp consisted of two earthworks , an inner and outer enclosure . When the site was excavated in 1901 several archaeological finds led to the camp being misidentified as Bronze Age . These finds , mainly pottery and flint knives , were excavated from a burial cairn discovered within the outer enclosure but the site has since been classified as from the Iron Age . 
