Excavations carried out in 1997 at the site of 58 to 59 Thomas Street and Vicar Street uncovered the remains of a furnace dating to the thirteenth century, a quiet reminder that this part of the city was working long before it became a cultural corridor.

The discovery was recorded by Carroll in 1998 and places industrial activity in this part of medieval Dublin at a period when the city was consolidating its urban form under Anglo-Norman influence. A furnace of this era would typically have been used for metalworking or the smelting of ore, processes that required sustained high temperatures and generated significant waste in the form of slag and ash. Thomas Street sits along one of the oldest routes out of the medieval city, and the area's proximity to craft and trade activity in this period is consistent with what archaeologists have found elsewhere in the Liberties, the historically distinct district that lay just beyond the old city walls and long associated with weaving, tanning, and metalwork. The 1997 excavation added a concrete, dated piece of evidence to that broader picture.

The site itself is not publicly accessible or marked in any visible way, and nothing on the surface signals what lies below. Thomas Street runs between James's Street and the junction near Christ Church, and the general area repays a slow walk for anyone interested in the layered history of the Liberties. The Dublin City Archaeology archive holds the excavation records for those who want to go further into the detail, and Carroll's 1998 report is the primary published source. The furnace itself remains underground, as most of medieval Dublin does.