Archaeological Trial Trench Evaluation at Radstone Fields, Brackley, Northamptonshire, December 2020-February 2021

The evaluation comprised the excavation of 44 trenches measuring 50m in length and 1.8m in width dispersed across the site (Fig 2). The rationale behind the placement of the trenches was to rapidly assess the archaeological potential of a wide sample of the site whilst targeting anomalies of archaeological interest identified by the geophysical survey. Their positions were subject to on-site constraints, notably the medium pressure gas main running along the central boundary. Trench 34 was realigned to respect the exclusion zone that was set up around the service. Trenches 40 and 41 were not excavated in their intended locations due to an error during fieldwork so Trench 41 was extended to investigate the curvilinear geophysical anomaly that the trench originally targeted. Trenches 18, 27, 32, 36, 40 and 43 were all extended slightly in targeted locations in order to gain a better understanding of the archaeological features that were encountered. Trenches were located using a Leica Survey Grade RTK GPS operating to an accuracy of +/-0.05m to Ordnance Survey National Grid and Datum. Trenches were machine-excavated using a flat toothless bucket measuring 1.8m wide under continuous archaeological supervision. The depth of excavation was sufficient to reach either the first horizon of archaeological remains or the upper interface of geological deposits. Topsoil and subsoil were stored separately on either side of the trench, at least 1m from the trench edges. Excavation did not proceed beyond safe working depths. Metal detectors were used to aid in the recovery of unstratified artefacts from trench spoil heaps and stratified artefacts from archaeological features (not discriminating against iron). The trenches were cleaned sufficiently to enhance the definition of features, unless it was certain that there are no archaeological remains present. All features were excavated to determine their date and character. Investigation slots through linear features measured a minimum of 1m in width and discrete features were half-sectioned. All archaeological deposits and artefacts encountered during the course of the evaluation were fully recorded. Recording followed standard MOLA procedures. Out of the 44 trenches excavated, a total of 22 contained features of archaeological interest. The remains identified form a continuation of the extensive Iron Age landscape that spreads across the northern periphery of the current Brackley settlement core, characterised during archaeological investigations at Brackley Sawmills, Brackley Foxhills and Northampton Road. The Radstone Fields evaluation area had a similar appearance to the nearby sites and comprised a substantial number of pits of varying form and function in addition to several roundhouses and possible post-built structures. The results of the evaluation have considerable potential to address the research priorities of the region and combined with the nearby investigations form a significant evidence-base of the Iron Age agricultural economy of the area.