2016:528 - 30 & 32-36 Thomas Street, Dublin, Dublin

Test trenching in advance of construction of student accommodation commenced at the site on 15 November and ran until 12 December 2016. This was carried out using a 13-tonne excavator fitted with a 1.8m-wide flat, toothless bucket. A total of 16 trenches measuring an approximate total length of 194m were excavated. Trenching ceased at the top of medieval layers, where encountered, or at the top of any structures or walls of medieval or post-medieval date. 

Archaeological deposits dating to the 12th–17th centuries were discovered across the site. Several layers of late medieval/post-medieval garden soils were identified throughout the site, occurring in places c. 0.4m beneath the present ground level. These overlay a layer of redeposited boulder clay imported onto the site sometime in the 13th/14th century, represented largely by a tan coloured gritty clay that occured c. 1–1.5m below present ground level (except where post-medieval/modern activity had resulted in its removal). Several pit and linear features of medieval date were found to cut this layer. This layer also overlay, in places, a black sulphurous smelling stony clay which extends from c. 1.6–3m below present ground level across large areas of the site. Further features of medieval date included a number of cut features (pits and ditches), a culverted watercourse which ran along the north of the site, clay-bonded walls in the eastern part of the site and medieval tanning pits, all identified at between c. 1.2 and 2m below present ground level.

Where it was possible to test below these medieval deposits, a jet black sulphurous smelling stony clay was encountered which contained infrequent fragments of Dublin-type ware and extended to c. 3m below the current ground level in places.

Two pieces of dressed medieval masonry were recovered, ex-situ, from post-medieval contexts. The first piece is a limestone double column base which is likely to have formed part of the cloiser of the Abbey of Saint Thomas the Martyr believed to have been located c. 50m south of the site (see attached plate). The second piece is a chamfered hood moulding of imported Dundry stone which presumably also originated in the abbey or alternatively came from the medieval parish church of St Catherine which was located c. 15m west of the site.

A series of post-medieval brick and stone walls, tanning pits, wells and demolition deposits were also identified across the site.

Excavation at the site followed on directly from testing and was commenced in January 2017 and is ongoing under licence no. 16E0054 ext.

Unit G1 Network Enterprise Park, Kilcoole, Co. Dublin