What survives of a medieval Augustinian priory on the south bank of the Liffey in County Kildare is, by any measure, the wrong kind of remains. The church, the cloister, the chapter house: all gone. What stands instead are the gatehouse, a postern gate, an outer gateway, and, perhaps most curious of all, a small tower in the north-east corner of the inner enclosure that appears to be a later folly, its walls stepping outward at first-floor level and its windows trimmed with Gothic-arch styling, decorative gestures with no defensive purpose. The priory was known as Scala Caeli, meaning Steps of Heaven, and it sits quietly on a gentle, north-facing slope above the river, hemmed in on one side by a small Liffey tributary and on another by a partially stone-faced fosse, a defensive ditch that once helped define the rectangular inner enclosure.

The priory was founded around 1205 by Richard, the first prior, and Adam de Hereford, for the Augustinian canons of St Victor, a reformed congregation of canons regular who followed the Rule of St Augustine and were known across medieval Europe for their intellectual seriousness. Its layout closely resembles that of the Augustinian priory at Athassel in County Tipperary, founded slightly earlier around 1200. St Wolstan's survived for roughly three centuries before the Dissolution of the Monasteries caught up with it: in 1536 Richard Weston, the last prior, was dispossessed of a site that included gardens, orchards, and cottages, and the property passed to John Allen, the Lord Chancellor. A fourth gateway, recorded on the Ordnance Survey six-inch map and drawn by A. Cooper in 1782 as a two-storied circular tower with a pronounced crack running its full height, fell around 1830, leaving no surface trace.

The main inner gatehouse is the most substantial thing left standing: a three-storied limestone structure, roughly eleven metres long, with a vaulted ceiling above the first floor, a guardroom off the main archway, and a spiral staircase in a small attached tower. The archway itself rises to around six metres, a considerable height that speaks to the ambition of the original complex. Farm sheds and a silage pit now abut it almost directly, which gives the site an atmosphere more agricultural than ceremonial. The outer gateway, about 180 metres to the south-east, still carries an archway of over four metres, with fragments of what may have been curtain walls extending from its angles.