2001:1187 - TONAFORTES, Sligo

Pre-construction testing was carried out at Tonafortes, where a hengiform monument was recorded. This monument, which has an overall diameter of approximately 85m, was to be partially affected by the proposed Sligo Inner Relief Road. The monument comprises a circular central area, 45m in diameter, enclosed by two banks and a ditch. Each bank averaged 8m in width. The site has a good view of Knocknarea and Queen Maeve’s Tomb to the west. Forty per cent of the site is within the land-take of the proposed project, and 10% will be directly affected by the actual road. It was decided that both land-take and road-take would be investigated. The land-take runs in a north–south direction across the monument. The eastern part of the monument would be excavated, while the western part will remain untouched.

Two test-trenches were opened by hand. The first was along the edge of the land-take, from the southern extent of the monument towards the centre. It measured 29m by 2m. It encompassed both banks on the south of the monument and the ditch. After removal of topsoil, the upper fills of the ditch were exposed. The width of the ditch averaged 12.4m. It had gradual break of slope and a concave base and appeared to be quite shallow but very wide. It averaged 0.8m in depth towards its centre. A possible cremation was exposed at the base of the ditch. Sparse to occasional fragments of burnt bone were visible. They were mixed with a very dark sticky grey silty clay, which contained a moderate amount of charcoal flecks. No definite archaeological features were noticed cutting the banks.

Test-trench 2 was opened in the centre of the enclosure and measured 3m2. It was approximately 1m to the east of the land-take. Aside from modern topsoil deposits and furrows, three possible phases of archaeological occupation were identified. The sod and the topsoil overlay a stone surface which covered the entire area of the trench. It was made up of mostly small and medium-sized stones (mostly subangular limestone averaging 50–60mm in diameter). It was exposed approximately 0.25m below ground level and was only one course thick. A large circular feature was exposed below the stone surface. The cut was 1.3m in diameter. This feature sloped fairly steeply to a depth of 0.7m and had a rounded base. Some chert débitage was uncovered within the fills. A stone fill was also investigated. This feature truncated two thick deposits. Natural boulder clay was exposed 0.7m below ground level. The edges of a cut were recorded cutting into this beneath the two thick deposits. It was then that full resolution of the site became necessary.

Test-trenches 3 and 4 were excavated in the area around the monument. Nothing of archaeological significance was recorded in them.

Test-trench 5 was opened on the crest of the hill near the monument, in a topographical depression consisting of a possible circular hollow averaging 16m in diameter. It was orientated north-west/south-east and measured 3m by 1m. After removal of the sod and the topsoil, the western edge of a cut was exposed, probably the edge of the circular depression mentioned above. The edge of the cut was very steep and the base appeared to be concave. It was cut into the natural gravel. It was filled with several topsoil-like deposits. Modern artefacts were retrieved from these fills throughout the cut.

Test-trench 6 was opened to the east of the enclosure, on a topographical anomaly. It was aligned north-east/south-west and measured 5m by 2m by 0.4m deep. The anomaly, a raised bank, approximately 3m in width, ran from the north-eastern corner of the field in a south-western direction towards the outer bank of the monument. After removal of the sod, a thick stone spread was exposed. This was probably used as a stone pathway. It consisted of small and medium-sized subangular and rounded limestone, very compacted in situ, mixed with a mid-brown sandy clay. Occasional large fragments of red brick were recovered from this spread, which indicated a modern date. The spread averaged 0.15m in thickness and overlay a potential archaeological deposit, a light to mid-beige sandy silt. No inclusions were recorded, except for a moderate number of stones. A slot-trench was dug through this deposit. It appeared to be quite irregular in depth. A stone deposit also lay on top of it. These two deposits appeared to be related to one another.

No archaeological deposits or structures were identified within Test-trench 7.

In Test-trench 8, two circular cuts, interpreted as possible post-holes, were identified in the north-west corner. They averaged 0.3m in diameter and were filled with a light to mid-grey medium-grained sand. Both averaged 0.3m in depth.

A series of trenches were mechanically opened to the south of the henge. Four were excavated in Zone 5 (Trenches A–D). Trench A measured 110m by 2.8m wide. Approximately 11m from its southern limit the remains of a fulacht fiadh were uncovered just below a layer of redeposited material. The spread consisted of a black sandy clay with frequent flecks of charcoal, a few small stones and occasional burnt stones. Although for the most part the spread appeared to be very thin, it reached 0.3m in thickness in some places. It averaged 7.45m long in a north–south direction. Its full extent remains unknown, as it extended beyond the eastern and western limits of excavation. The remains were left in situ for further investigation.

In Trench B, approximately 32m from the southern limit, a series of sandy deposits were recorded. They appeared to be quite irregular in dimensions and depth. It was not possible to determine whether they were of natural or of artificial origin. In the northern part of the trench, where it curved in an eastern direction, the remains of modern furrows were exposed. They ran in a north-west/south-east direction towards the henge.

Nothing of significance was found in Trenches C or D.

Several test-trenches were mechanically opened in an area covering the immediate landscape to the north, north-east and north-west of the henge; little of archaeological significance was noted in them. Two probable land drains were exposed to the west of Trench F, filled with rubble material and frequent fragments of red brick. They averaged 0.3m in width. A series of modern linear cuts/furrows were exposed in Trench H. A linear cut was exposed approximately 57m to the west of the eastern limit of the trench (see description below, as cut continued towards and across Trench K). Approximately 68m to the west of the eastern limit of Trench H, a linear feature containing dark and burnt material was investigated. The fill, which was truncated by the furrows, consisted of a dark silty sand with burnt stones and charcoal. It averaged 4.2m in width and extended beyond the northern and southern limits of excavation. It reached 0.22m in depth. Modern finds were found within the upper fill but there was a possibility of contamination owing to the presence of modern furrows. Approximately 77m from the eastern limit of the trench, the substrate dipped to a depth of at least 2m. This zone was filled with modern material and rubble, silage and wood. This zone of fills continued for 30m in a western direction. This could have been the location of a possible pond which was filled in recent times.

Further to this zone of disturbances and modern features, investigations were carried out along the proposed slip-road. Several potential archaeological features, disturbed by modern activities, were exposed. Approximately 113m to the west of the eastern limit of the trench a circular cut was exposed. It was approximately 3m wide (east–west). The full dimensions are unknown as the feature extended beyond the southern limit of excavation. The known depth reached 0.3m. No artefacts were retrieved from the dark fill. At 138m from the eastern limit of the trench a linear cut ran across the trench in a north–south direction. It was 3m wide and reached a maximum depth of approximately 0.6m and was exposed 0.4m below ground level. It had four different fills. At 150m from the eastern limit of Trench H a circular pit was exposed, extending beyond the northern limit of excavation. This cut contained a few sherds of modern pottery as well as shell, glass fragments and slate.

In the eastern part of Trench I a cobble surface was exposed, with well-set large cobbles. It measured 2.8m east–west and extended beyond the northern limit of excavation. It had a straight edge on the south. It seemed to be one course thick and overlay a light grey sandy silt. No definite date could be established for this surface.

A possible circular pit was investigated in Trench J. It was 5m in width (east–west) and extended beyond the northern limit of excavation. It had several dark fills. The known depth reached 0.4m. Modern sherds of pottery were retrieved from the upper fills. There was a possibility of intrusive finds owing to the presence of cultivation furrows in the area. Two small burnt pits/spreads were exposed to the east of the pit. The first averaged 0.45m in length (east–west) by 0.25m and was 0.09m deep. It contained frequent flecks of charcoal but no definite datable artefacts. The second spread averaged 0.65m in length (east–west) by 0.35m. It extended beyond the northern limit of excavation and was 0.15m deep. It had the same composition as the first spread. At the eastern limit of excavation a large ditch feature was investigated. It was filled with a very dark silty sand. It was 3.5m wide on top of the cut and 0.9m at the base. It ran across the trench and was 0.5m in depth. Pieces of metal objects were found at the base of the cut. It appeared to be associated with modern activities and disturbances recorded in the vicinity.

The investigation of the proposed slip-road, on the west of the area, showed a great density of features. Some of these appeared to be associated with modern activities. Other features were exposed in this portion of the zone. The date, nature and full density of the archaeology is still uncertain. No artefacts were retrieved from the majority of the features. Trench K extended through the north-eastern part of the area. Two linear cuts were investigated throughout the trench. The first was 0.6m wide and 0.35m deep, and ran in a north-east/south-west direction. It had a ‘U’ shape and deepened towards the north. Modern finds were retrieved from the upper parts of the fill, but several modern furrows also extended in this part of the zone, which could indicate modern intrusion. The second cut seemed to be a continuation from a linear cut exposed in Trench H (above). It ran north-east/south-west across the trench, and was 1.6m wide by 0.5m deep. The fill was a dark brown silty sand with charcoal flecks. No definite datable finds were found. It was supposed that this feature might be the remains of a post-medieval field boundary.

Apart from the archaeology uncovered inside the ceremonial enclosure, a large number of features were recorded throughout the field, which is to be affected by the road project. Several modern occupations were also recorded. The eastern and southern part of the field and the monument were also disturbed by activities related to the roadworks of 1997. Several recommendations related to a resolution were issued to all relevant bodies.

Horge House, Camp, Co. Kerry