In June 2023, a community excavation in the churchyard of Caerwent church set out to try to answer two questions.

• What was the line of stones poking through the grass to the east of the east end of the parish church? First seen after dry weather about 10 years ago, nobody seemed to know what they were. They did not line up with the Roman town grid or the existing parish church.

• Was there evidence for a former side chapel on the north side of the church’s chancel, suggested by an early watercolour of the church?

To investigate these questions two trenches were opened by members of Caerwent Historic Trust, Amgueddfa Cymru volunteer scheme, Shirenewton Local History Society and Ss Stephen and Tathan’s Parish Church, Caerwent.

It was quickly established that the areas had been investigated during the early 20th century excavations of Caerwent. Done in the final year of these excavations, in 1913, the work had, however, never been published. This was probably due to funds running out following the death of their patron, Lord Tredegar, in that year, and then the start of World War One just a year later. The line of stones turned out to be the top of a revetment wall constructed by the Edwardians to allow a drain from the Roman Municipal Bath House to be viewed. The hole had in fact remained open until 1965, when it was backfilled with building rubble in during the remodelling of the sanctuary of the church.

The trench to the north of the chancel revealed some features consistent with there once having been a structure to the north of the chancel and also one wall of a Roman building, consistent with that recorded by the Edwardian excavators as part of House XXVIs.