1992:161 - HOLY TRINITY ABBEY, Trinity Island, Roscommon

Excavations, in advance of conservation and funded by the Office of Public Works, were completed in 1992 with a 2nd season of 16 weeks duration. The abbey comprises the church, the sacristy adjoining the north-east end, and the east range of the claustral buildings to the south. No evidence for any other structures was found on the island.

The 13th-century church measured 33.1 m long internally, revealed by excavation at the west end, where the original foundation for the wall was uncovered at the north. The west wall was partially extant to the south. In addition, beneath a quoin at the original south-west corner, the foundation shows 2 construction phases. The later west wall was built on the outside of the original, thereby increasing the masonry width to c. 2.5m and forming a small tower to both north and south. Excavation also revealed that a plan to build a wall across the church, c. 3m from the original west end, was not carried out.

The sacristy was found on excavation to be a 2 period building. The initial structure, probably dating to the 13th century, measured 4.4m x 5.5m internally. The southern section of the west wall is original and the foundations for the east and north walls were exposed. The building was extended northwards and the later east wall was constructed inside the original one, making the internal dimensions of the sacristy 6.8m x 4.5m. An ogee-headed window and the use of pock dressing indicate a 15th-century date. The north portion of the later sacristy disturbed existing burials associated with the use of the earlier sacristy.

The east range was fully excavated. It was built as a unit with internal dimensions of c. 21.1m x 6.1m, and divided into 5 chambers on the ground floor. Excavations within the northern chambers, measuring 4.5m in length, were completed in 1992. The north-west chamber, 2.3m wide, has a west doorway and a north-east chamber, 3.1 m wide was lit by an east window. The dividing wall has a blocked doorway and at its south end, a hatch. The chapter room, the largest chamber in the range, measured 8m x 6.1m. Three doorways, 2 at the west and 1 at the east provided access. At the southern end of the range, 2 chambers, both the width of the range, with an interconnecting doorway, were revealed. The smaller chamber to the north, measuring 2.2m north to south, has a narrow east window and a hatch in the cross-wall to the chapter room. The south chamber, c. 3.9m long, had a west doorway.

A garderobe was added to the south end of the range–the usual location for this structure which was connected to the dormitory on the 1st floor. This well-preserved building, standing to a maximum height of 4.1m, measures 2.75m x 1 .2m internally. An outlet was provided through the base of the south wall. The opening, 0.78m x 0.5m on the interior, which had a single lintel and squared jamb, abutted the east wall. To the south of the garderobe, the ground sloped down to the lakeshore. Here, a soak-away was uncovered for the effluent from the garderobe. It consisted of randomly scattered unhewn stone covering an area c. 3m x 4m.

One hundred and sixty-nine human burials were recorded this year. They were found inside the east and west ends of the church and within and surrounding the sacristy. The area east of the east range was also used as a burial ground and interment had taken place within the northern chambers and the chapter room. The majority of the burials were in shallow pits, which were unmarked when excavated.

The more unusual finds comprised gilt-bronze and silver pieces which probably formed the stem of a chalice, a silver stirrup-shaped finger ring of 13th–14th-century date, and an ivory (?) handle with a silver terminal decorated with medieval vine scroll. Two 13th-century silver coins were found. The bronze finds included a medieval ring brooch, a strap-tag and an 18th-century shoe buckle. The iron implements consisted of a well preserved shears, a slean, 4 knives and 2 pruning hooks. In addition, an iron buckle, 2 horseshoes, a binding strip, over 400 nails and iron slag, were recovered. A single sherd of medieval pottery was found. The remaining pottery and glass date from the 18th century onwards. A substantial number of rotary querns were found, 2 of which are decorated.

Templemartin, Craughwell, Co. Galway