The Augustinian Priory of St. Thomas the Martyr once commanded thousands of acres, multiple castles, and a sprawling complex of buildings, yet today its presence is confined to fragments uncovered during road works and construction projects, a cobbled floor here, a stretch of walling there, seventeen burials at Hanbury Lane.

The priory was founded in 1177 by Henry II, a foundation widely understood as an act of penance in the aftermath of Thomas Becket's murder, and it quickly became one of the most consequential ecclesiastical establishments in the city. Its ambitions were considerable even by the standards of the age. In 1250, Henry III had to intervene personally after the Mayor of Bristol seized a shipment of stone intended for the abbey church, diverting it instead to build a castle, and ordered it returned to the canons. By the time of the Dissolution in 1539, the priory's holdings amounted to roughly 2,300 acres, two manors, three castles, and a variety of smaller properties including shops and cottages. In 1545, the monastery and its lands passed to William Brabazon, and by 1610 John Speed's map of Dublin records the site simply as Thomas Court, the ecclesiastical identity already fading into a place name. Archaeological work in the 1990s began to recover what remained: a twelfth-century boundary ditch seven metres wide and one and a half metres deep was identified in 1995, along with decorated floor-tiles. The following year, the south wall of the church was exposed at Meath Market, still associated with ceramic pavements laid in situ. Excavations at Hanbury Lane in 1999 produced clay-bonded walling, Dundry stone (a distinctive oolitic limestone imported from Somerset and commonly used in high-status medieval buildings in Ireland), and line-impressed tiles.

The area around Thomas Street and the Liberties repays slow, attentive walking. The topography itself is suggestive, with slight rises and dips in the streetscape reflecting buried medieval features. There is nothing to see above ground at the priory site as such, but the neighbourhood holds other medieval layers close to the surface, and knowing that a ditch marking the boundary of a royal foundation from 1177 lies a metre or so below the pavement gives an ordinary street a different quality entirely.