Oswestry Castle Excavation May 2017
The September 2016 excavation demonstrated that the outer faces of the Keep walls run right to the edge of the Victorian revetment walls that surround the upper level of the Castle mound. However on part of the Northern wall there is an inset that may have been created to allow room for a bench seat. Part of the revetment wall here, although in poor condition and crudely repaired, has the characteristic 60 degree slope of the splayed base, noticeably different to the vertical revetment walls either side. It is possible that this may be an exposed part of the North facing splayed base of the keep, and a short 1 week excavation in May 2017 attempted to prove this.
Four courses are visible above the level of the path surrounding the mound, and a trench was excavated in two parts (Trench 5E and 5W) with a baulk left between them. The path here is narrow which restricted the depth we could excavate, particularly in Trench 5E. In Trench 5W we were able to excavate deep enough to expose the bottom course of the wall. This revealed 9 courses of the now characteristic well shaped sandstone blocks set at 60 degrees, and the blocks below ground level are in much better condition than those above. Also the bottom course is of smaller blocks with two faces, the lower face being vertical with clearly visible foundations below this. Time and space constraints prevented any further excavation to examine the nature of the foundations.
Trench 5E had even tighter space restrictions and we were unable to excavate to the foundation level. However we did find one of the sandstone blocks with a curious ‘V’ shaped chamfer at one end which is similar to those found on ‘clamping buttresses’ seen on many square keeps and church towers of the 12-13th century. This block is part of the fourth course from what we think is the top of the splayed base and eight blocks away from the Eastern edge of the base, which suggests a substantial clamping buttress. The buttress itself would have risen vertically from this course and would extend outwards from the vertical Keep wall by 0.5m or so. Unfortunately this Northeast buttress has been damaged, presumably in Victorian times, to allow for the laying of a substantial lead water pipe so we cannot identify it’s Eastward extent accurately. So far the North Western and North Eastern corners of the Keep have been found to be damaged so our next excavation in September 2017 will be sited to locate and examine the South Eastern corner and hope that this one is intact!
There were very few finds from this trench but a small amount of pottery was found next to the lowest course in Trench 5W. This was very similar to green glazed pieces of Medieval pottery found in Trench 4 in September 2016 (we are still awaiting an expert report on these) and may even be from the same pot. This demonstrates the degree of disturbance caused by the landscaping and backfilling of the site in the past, and because of this we have not yet excavated a securely sealed context with datable finds that might tell us when the castle was built.