On the gently sloping western side of the Moel Ton-Mawr summit plateau are the earthworks of diamond-shaped concentric hillfort, associated with wider-spreading field systems no doubt of Iron Age date.
The complex consists of a subrectangular enclosure 75-80m east-west by 60-65m. It occupies the central southern part of a larger, more irregular enclosure that is roughly 230m east-west by 195m. This may also have been intended to appear rectilinear despite the concave north-eastern facade which rests on a stream channel. Both enclosures are defined by double banks with medial ditches. This suggests that they are broadly contemporary. Both have south-facing entrances, the outer offset by some 20m to the east. These are connected by further banks and ditches, producing a forecourt or approach way.
A third, newly recognised, enclosure is attached to the south side of the outer circuit and is a more visible survivor of a larger field system. This is rectilinear, roughly 145m east-west and in the region of 80-100m deep. It too appears to be defined by double banks with a medial ditch, at least on its south side. Its eastern side springs from the west side of the outer enclosure entrance and there appears to be an embanked trackway on this side. This would be the main approach to the complex and it extends beyond the third enclosure.
Source: RCAHMW Glamorgan Inventory I.2 Prehistoric & Roman (1974), 57, fig. 32, No. 692
John Wiles 13.12.07, revisions by T. Driver, 2nd March 2011