Along the roadside at Kilteel in County Kildare, a fragment of a high cross marks the edge of what was once one of the more strategically consequential religious houses in medieval Ireland. The Knights Hospitaller, formally the Knights of the Order of St John of Jerusalem, a crusading military order that also ran hospitals and hospices across Europe and the Holy Land, established a preceptory here, meaning a local administrative and residential house of the order, on ground that had already been sacred for centuries. Beneath the Hospitallers' foundations lay the remains of an early Irish monastery known as Cell céli críst, the church of the servants of Christ, a lineage the incoming order would almost certainly have been aware of, even if they left no written record of it.

The preceptory was founded sometime before 1212 by Maurice Fitzgerald, though no foundation charter or original grant of land has survived. The earliest firm documentary reference comes from the Justiciary Rolls of 1308, and by the 1320s and 1330s the site was significant enough that three general chapters of the order were convened here, in 1326, 1333, and 1334. Its importance was not purely spiritual. From the 14th century onward, Kilteel sat on the frontier between Gaelic Irish territory in Wicklow and the Anglo-Norman world of Kildare and Dublin, and it appears to have shaped the very line of the Pale Boundary, the earthwork and ditch that defined the limits of effective English colonial control, a portion of which ran immediately south and west of the preceptory. A tower house with an attached gatehouse and a possible bawn, an enclosed defensive courtyard, was added at the north-west corner of the complex in the 15th century, sharpening the site's defensive character considerably.

What survives today is fragmentary and, in places, barely readable as architecture. The roughly rectangular enclosure, approximately 200 metres by 150 metres, is defined by a low inner earthen bank, a narrow fosse, and a broader outer bank, elements confirmed by a small excavation carried out in 2002. Two gatehouses remain in partial elevation on the valley floor, the better-preserved of the two retaining two columns of rubble masonry, a gate-arch of undressed voussoirs, and, at first-floor level, a tiny vaulted guard room now inaccessible to visitors. The ruined building within the enclosure preserves walls standing to around 4.5 metres, with the outlines of semi-pointed arched window embrasures still just legible in the masonry, their facing stones long since robbed out.