On a south-west-facing slope in Drumlummin, County Tipperary, where the land tilts down towards the River Tar, a reclaimed meadow conceals what was once a roughly circular enclosure somewhere between 35 and 45 metres in diameter. By the time anyone looked closely enough to record it properly, the bank, never much more than 40 centimetres high, had become invisible across its western arc. The whole thing was effectively gone from the surface.

The enclosure came to light not through deliberate archaeological investigation but as a consequence of advance survey work carried out ahead of the Cork to Dublin gas pipeline in 1981. Field survey recorded the curving earthen bank before construction began, and a magnetometer survey, a technique that detects buried features by measuring variations in the soil's magnetic properties, revealed an external fosse, a defensive ditch, that no longer registers at all on the surface. That combination of a low bank and an outer ditch is characteristic of the kind of enclosed farmstead or ringfort that was a common form of rural settlement in early medieval Ireland, though the notes do not assign a firm date to this particular example. What makes the Drumlummin enclosure especially interesting is its immediate context: a castle lies roughly 55 metres to the east, and a mid-17th-century house sits about 40 metres to the north-east. Three distinct periods of occupation, or at least of building, within a very small area of one sloping field, each one presumably aware of what came before it.