When engineers were laying the Luas light rail line along Mary's Abbey Street, a southern section of the precinct wall of St Mary's Abbey was briefly uncovered before being reburied beneath the city once more. It is a reminder that the street's name is not merely decorative, and that the ground underneath carries a great deal more history than the surface suggests.

St Mary's Abbey was a Cistercian foundation, and the Cistercians were a reform movement within Benedictine monasticism, known for establishing their houses in deliberately remote or marginal locations and for the austerity of their architectural and devotional practice. By the twelfth century, the abbey had become one of the most powerful religious institutions in medieval Ireland, controlling extensive landholdings and exercising considerable political influence in the region. The precinct wall, a section of which surfaced during Luas construction work, would have defined the boundary of that monastic world, separating the regulated life inside from the city growing up around it. The detail about the wall's exposure comes from a personal communication by Frank Myles, and was compiled for the archaeological record by Geraldine Stout in August 2012.

The most substantial visible remains of the abbey today are found in a vaulted chamber off Meetinghouse Lane, a short walk from the street in question, and that fragment is well worth locating. The chapter house, as this surviving room is identified, is managed as a heritage site and is open to visitors on a limited seasonal basis, so it is worth checking access before making a specific trip. Mary's Abbey Street itself gives little away; the Luas line runs along it quietly, and there is nothing to mark where the precinct wall briefly reappeared. Knowing that the medieval boundary once crossed underfoot, and that it may still be there inches below the tarmac, lends the ordinary street an odd kind of weight.