It does not appear on any edition of the Ordnance Survey six-inch map, the standard cartographic record that has documented Irish landscapes since the nineteenth century, which makes its identification all the more dependent on the kind of overhead scrutiny that only became possible in the twentieth century. The enclosure came to light through Ordnance Survey aerial photograph 2350/1, which captured the outline of a rectangular feature that ground-level survey had simply never recorded.

What purpose the enclosure served is not stated, but the presence of a ring-ditch roughly twenty metres to the west-north-west adds a layer of context worth noting. A ring-ditch is the term used for a roughly circular ditch, often all that survives of a burial mound or barrow once the earthen mound above it has been ploughed or eroded flat over centuries. The pairing of a rectangular enclosure with a nearby ring-ditch is not unusual in the Irish landscape, where field boundaries, settlement features, and funerary monuments were often established in proximity to one another across the prehistoric and early medieval periods. Whether the two features at Tulla are related in date or function is unknown, but their close spacing in an otherwise unremarkable stretch of pasture suggests the area repays attention.