It is easy to walk past without a second glance, yet the object may be considerably more interesting than it appears: it is thought to have served as a medieval fish tank, a practical piece of monastic infrastructure rather than a decorative one.

The trough sits to the north of the east gable of the 13th-century Dominican friary at Lorrha, a site with deep ecclesiastical roots in this part of north Tipperary. Medieval religious houses, particularly those of the mendicant orders such as the Dominicans, often maintained fish tanks or vivaria to keep live fish fresh for the table, especially during the many fasting days in the liturgical calendar when meat was forbidden. The trough's position is suggestive: it lies roughly halfway between the friary and a 13th-century mill that once stood nearby, placing it within a cluster of medieval working structures that would have formed the practical, unglamorous backbone of monastic life. Whether the limestone basin was purpose-cut for holding fish or adapted from some earlier use is not recorded, but its dimensions, a depression measuring 0.35 metres by 0.7 metres set into the larger block, are consistent with containing water and its inhabitants.