By 1986, something that had survived for centuries in a field beside the Sweet River in County Kildare had effectively ceased to exist at ground level. Fourteen years earlier, in 1972, it had still been detectable as a roughly rectangular earthwork, some 42 metres east to west and 26 metres wide, defined by an inner earthen bank and an outer fosse. A fosse, in this context, is simply a ditch, typically dug to throw up the bank beside it, and together the two features would have formed the boundary of an enclosure of the kind common throughout early medieval Ireland. The interior was described at the time as very uneven and tree-planted, suggesting that whatever structures or activity the enclosure once contained had left the ground lumpy and disturbed beneath the canopy.

Enclosures of this type are among the most widely recorded but least understood features in the Irish landscape. They range in date across many centuries and served many purposes, from settlement and agriculture to ritual or boundary marking. This one, sitting in level pasture just south of the Sweet River, left no documentary trail that has survived, and no excavation appears to have been carried out before it disappeared. The fourteen years between its 1972 description and its apparent erasure by 1986 likely saw the land levelled for more intensive agricultural use, a fate that claimed a great many earthworks across Ireland during that period of land improvement and drainage. What had been a legible, if worn, feature became simply a field.