What looks at first like uneven pasture ground is in fact the ghost of an organised farming settlement, a field system stretching roughly 240 metres north to south and 120 metres east to west, its walls still legible beneath a thin skin of peat.

The system is what archaeologists call a pre-bog field system, meaning it was already in use before the blanket bog formed over it. Such landscapes are found in several parts of Ireland and typically date to the Bronze Age or earlier, preserved precisely because the encroaching peat sealed them rather than destroyed them. At Ballagh, the best-preserved section lies at the southern end, where collapsed field walls push up through the peat in long stretches. The main east-west wall at this southern boundary runs around 110 metres, with two further walls branching away to the northwest at lengths of roughly 35 and 70 metres respectively. Additional walls extend and turn, one of them forming a rough inverted U-shape in the western portion of the system, with upright stones of about half a metre in height set at irregular intervals along its course. Crucially, the walls appear to sit on clay beneath the bog, confirming that the ground was worked before peat accumulation began. Within the overall system there are ten associated hut sites, the remains of what was once a functioning settlement, not just a patchwork of enclosures but a place where people actually lived.

The southern end of the system, where the peat cover is thinnest and the walls most visible, is the clearest point of entry into reading this landscape. The upright stones along the inverted U-shaped wall are a detail worth looking for, their irregular spacing suggesting something less standardised than a later field boundary and possibly reflecting the working practices of whoever maintained this ground long before the bog closed over it.