A series of crop-marks which looked like enclosures, were revealed by air photography in the Blackwater Valley, Co. Cork in 1989. In order to learn more about these sites, one, Conva, Co. Cork, was chosen for limited excavation. Repeated ploughing had extensively levelled the area. Despite this, a three-dimensional topographic survey was carried out initially as an attempt to determine the nature of the various enclosures. In addition, a combination of resistance, magnetometer survey and ground radar was employed. Due to the presence of ploughed soil and related factors only limited information came to light.
Excavation was concentrated on a complex of three enclosures which varied in shape and size. There was also a series of large pits in the area. It is difficult to establish the relative chronology of the enclosures and pits. However, it appears that the various features may have taken place in quick succession. Finds were few and undiagnostic, iron slag and furnace bottoms being the most common. The function and purpose of the sites is also problematical although it is possible that Enclosure 2 was a small ringfort. The radiocarbon dating evidence ranges through Early Christian and Medieval times.