2002:0386 - CORRSTOWN, Derry

After an initial assessment in winter 2001, a second- phase assessment was undertaken at a greenfield site at Corrstown, Hopefield Road, Portrush. The assessment consisted of the mechanical excavation of 22 test-trenches. The proposed development site lies within the southern limits of Portrush town, consisting of an area of 7.4ha comprising four arable fields, with existing housing along the western, northern and north-eastern sides of the site.

Testing began in the northern Field 4, which was rectangular, measuring 141m north–south by 152m (maximum), and contained a recorded cropmark enclosure. Geophysical survey undertaken across the cropmark location revealed much background noise in the form of the igneous geology; however, a number of anomalies of apparent archaeological or artificial signature were visible, including what appeared to be the incomplete ring of a circular enclosure over the approximate location of the cropmark site.

Extensive topsoil collection was undertaken in January 2002 before the Phase 2 assessment. Eight test-trenches (Trenches 5–12) were mechanically excavated in Field 4, revealing numerous features of archaeological potential. Trench 5, 77m long and 1.9m wide, ran east–west along the northern side of the field. It was characterised by dark brown topsoil, 0.25–0.3m deep, over orange/brown, sandy clay subsoil. Five pit features and one narrow linear gully were revealed, along with an apparent irregularly shaped spread of stone mixed with mottled orange/brown clay across the western half of the trench.

Trench 6, a perpendicular extension south of Trench 5, was 33.6–35.5m from the eastern end of the parent trench. It was 27.5m long (north–south) and 1.9m wide and was characterised by dark brown topsoil, 0.25–0.3m deep, over orange/brown, sandy clay subsoil. Features revealed included a curvilinear gully with associated pits, a possible cobbled or metalled surface and two east–west-aligned linear features, one of which was clearly an early modern drainage channel. The most significant of these features was the curvilinear gully, F10, which extended beyond the test-trench to the west and represented the eastern half of a structure estimated to be at least 7.2m in diameter. This feature consisted of a gully or slot-trench, 0.6m wide, filled with black/dark brown, clayey silt containing charcoal flecks and numerous packing stones, particularly along the inner west side. A large coarseware rim/body fragment of Late Bronze Age character was recovered from its upper fill. Within the curvilinear gully two features survived: F11, an elongated pit, and F12, a small circular feature, most likely a post-hole. These features are the remains of a possible Late Bronze Age round house or hut.

Trench 7, running east–west across the centre of the eastern side of the field, was 34m long and 1.9m wide. Trench 8 extended north–south across the line of Trench 7, 24–26m from the eastern end of parent Trench 7, and was 35.5m long and 1.9m wide. Dark brown topsoil survived on average 0.3m deep over orange/brown, stony clay subsoil. A linear gully, a pit and a section of a curvilinear gully were revealed; the last represented the remains of the cropmark enclosure and was traced into Trench 8. The curvilinear gully/ditch, F17, extended north-east/south-west through Trench 7 into Trench 8. A length of c. 8m was exposed (north-east/south-west), surviving to 0.7–1m wide and filled with dark brown/black, clayey silt containing numerous round and angular stones, although it is not readily apparent whether these are packing stones. The surviving arc suggested a circular or oval enclosure c. 25m in diameter; however, no clear trace of the northern or western arcs of the gully/ditch could be found within the western end of Trench 7 or the northern end of Trench 8.

Trench 9, running east–west along the south-central area of Field 4, was 128m long and 1.9m wide, with two extensions (Trenches 10 and 11) running north of the trench, 75.15m and 80.6m from the eastern end. The trench was characterised by dark brown topsoil, on average 0.3m deep, over orange/brown, sandy clay subsoil with patches of stone concentration. Four linear features, four pits, a linear metalled surface and the remains of the northern end of a north–south-aligned rectangular house foundation were revealed. The foundation trench, F27, revealed the northern end (3m in extent) of a north-west/south-east-aligned rectangular structure, 5m wide externally, with an estimated internal width of 3.5m. No finds were recovered from the upper fill of the feature; however, it was felt that, because of its type and dimensions and the fact that structures of Early Christian date had been recovered in the adjacent site at Magheramenagh excavated by Stephen Gilmore in 2000 (Excavations 2000, No. 164, AE/00/41), this most likely represents an Early Christian rectangular house.

Trench 10, 24m long (north–south) and 1.9m wide, contained four south-east/north-west-aligned linear features and a possible pit. Trench 11, 22m long (north–south) and 1.9m wide, contained part of a large oval feature, possibly a pit, and an oval spread of charcoal-rich soil.

Trench 12, running east–west along the southern side of Field 4, 127m long and 1.9m wide, was characterised by dark brown topsoil on average 0.3m deep over orange/brown, sandy clay subsoil with patches of stone concentration. Four circular pit features and three north–south-aligned linear features were revealed.

Field 3 was rectangular, measuring 110m north–south by 190m (maximum). Five test-trenches (Trenches 13–17) and continuations of two Field 2 trenches (Trenches 18 and 19) were mechanically excavated through Field 3. Features of archaeological potential were revealed only in Trench 15. All trenches were excavated by a mechanical digger with a ditching or grading bucket.

Trench 15, running north–south at the north-central area of the field, was 54m long and 1.9m wide. It was characterised by dark brown topsoil 0.25–0.3m deep over orange/brown, sandy clay subsoil. The trench revealed a post-medieval linear drain and a further, slightly curving linear feature of archaeological potential: A north–south-aligned linear feature, F46, slightly curving toward the south-west, was found cut into subsoil and extended through the trench, 19–24m from the northern end. The feature survived to c. 0.8m wide and was filled with dark brown, compact clay containing occasional large stones. The northern end of this feature was uncertain and may have been truncated by later ploughing, and the southern end exited the western section of the trench 24m from the northern end.

Field 2 was rectangular, measuring a maximum of 96m north–south by 174m, lying south of Field 3. Phase 1 Test-trenches 2–3 were positioned east–west and north–south along the eastern 30m littoral of the field. Surface collection, of mostly lithic finds, was undertaken across the field, which was subdivided into quadrants for recording purposes. Five test-trenches (Trenches 18–22) were mechanically excavated through Field 2, of which two continued into Field 3 (Trenches 18 and 19) and one into Field 1 (Trench 22). No features of archaeological potential were revealed.

Field 1 was rectangular, measuring a maximum of 94m north–south by 164m, and lay south of Field 2. Phase 1, Trench 4, was positioned north–south through the eastern 30m littoral of the field. Surface collection, of mostly lithic finds, was undertaken across the field, which was subdivided into quadrants for recording purposes. Five test-trenches were mechanically excavated through Field 1 (Trenches 22–26), one of which extended south from Field 2 (Trench 22, above). No features of archaeological potential were revealed.

The results from Field 4 were very significant. From eight trenches, 44 features were recorded, comprising 21 possible pits, two curving gullies, seven north–south-aligned linear features, seven south-east/north-west-aligned linear features, two east–west-aligned linear features, three possible metalled surfaces, a south-east/north-west-aligned rectangular structure and an area of stone or disturbed bedrock.

The type and number of features revealed in Field 4 suggest that this northern area of the proposed development has significant archaeological potential. Three main concentrations of features suggest several possible Late Bronze Age round houses in the northern and eastern quadrants of the field surrounded by associated features, as well as at least one rectangular structure, possibly of Early Christian date, in the south-west quadrant. Because of the proposed density of housing planned for Field 4 and in the light of the developer’s reluctance to avoid this area of archaeological potential, full excavation of the field was recommended in agreement with Built Heritage, DoE (NI).

Monitoring of topsoil removal from Fields 1 and 2 during spring/summer 2002 led to the recovery of further large amounts of lithic material; however, with the exception of several land drains and an isolated pit-like feature of undetermined date or function, no archaeological remains of any potential were revealed in these areas.

Excavation of Field 4 and parts of Field 3 was planned for late autumn 2002–spring 2003. Preliminary results of that excavation, undertaken under licence AE/02/100, are detailed in Excavations 2002 (No. 387).

Unit 21, Boyne Business Park, Greenhills, Drogheda, Co. Louth