An oval enclosure once occupied level ground on the valley floor, measuring roughly 18 metres north to south and 24 metres east to west, a modest but distinct feature that would have been legible in the landscape to anyone who knew to look. By 1987, it had been levelled entirely, absorbed into the reclaimed grassland around it. Nothing marks it at ground level today.

The enclosure first appears on the Ordnance Survey's six-inch map of 1839, the great systematic effort to record the Irish landscape that remains one of the most remarkable cartographic achievements of the nineteenth century. It was still present on the 1900 revision of that map, meaning it survived, in some form, for at least six decades after it was first formally noted. A second enclosure lay approximately 30 metres to the north and shared a similar fate, also levelled and invisible today. By the time of the 1900 survey, a new undulating field boundary running roughly northwest to southeast had been built between the two sites, a boundary that post-dates the original mapping and now sits just south of where that northern enclosure once stood. The two features, whatever their original purpose, were gradually erased by the ordinary pressures of agricultural improvement.

Enclosures of this kind are common across Ireland, the word covering everything from early medieval farmsteads to prehistoric ceremonial sites, their precise function often impossible to determine without excavation. What makes Gaulstown quietly melancholy is how thoroughly the record has closed over. The maps document the shape; the field shows nothing. The only evidence that something was here is cartographic, a pair of outlines on nineteenth-century paper that outlasted the earthworks themselves by well over a century.