Re-assessing Harrod and Spurden

Harrod's survey

A plan of the Bromholme ruins (right) was published by Henry Harrod FSA, in 1857 (Gleanings Among the Castles and Convents of Norfolk, p. 220) and was a combination of his own survey made in 1854 together with a plan made by Mr Spurdens in 1822 when the remains were more extensive.

An assessment of the plan in terms of how accurately the remains were recorded can be made using recent LiDAR and drone surveys of the sight.

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LiDAR image of the ruins at Bromholme

Produced by the Environment Agency, the LiDAR Composite DSM (Digital Surface Model) is a raster elevation model covering areas of England at 25cm spatial resolution and is available through the Government’s open data scheme.

The LiDAR data file used was tg3433_DSM_25CM.asc, and visualised using QGIS version 3.6.2-Noosa. The image below shows the LIDAR render of the site with the extant remains clearly visible to the right of the image.

The buildings of the current farm can be seen towards the bottom, with the trees visible as bright reflections.

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Image of the extant remains 3d model

The drone survey was commissioned by Paston Footprints and the resulting imagery and 3D model was generated using Agisoft PhotoScan.

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By using a combination of the LIDAR and photogrammetric 3d model, the alignments of the existing remains can be extruded and compared with the Harrod plan. The image below left shows the LIDAR/3D model and the extrusion of wall lines, the image right shows the Harrod plan overlaid to scale.

The existing visible remains suggest 4 differing alignments, some more acute than others. Clearly the tower and southern wall of the Nave alignments stand out as being different, whereas Harrod had them on more or less the same alignment with the choir at a slightly different angle. That said, the Harrod plan is very accurate in terms of scale and only needs a little tweaking to address the alignment issues, the results of which can be seen on the image below left.

It has been possible to combine Harrod’s plan with the 4 main alignments to show how the remains most likely appeared to Harrod and Spurdens.

It appears that the Dormitory was not as angled as much off the Chapter House as indicated by Harrod and was pretty much aligned with the Nave and Cloisters.

The Chapter House (red) is very closely aligned to the Choir, if not on the same alignment, as well as the Refectory (yellow), but it is the Nave, Dormitory and Cloisters (green) which seem to share a common alignment.

It is interesting to note that there are indications that the ruins seem more extensive than initially appear.

For example, in the image right, which overlays the re-aligned Harrod plan to the photogrammetric model, there seems to be raised areas of vegetation on or near some indicated wall lines just south of the refectory.

The re-aligned Harrod's plan (left) was used as the keystone to the Bromholme reconstruction and will be the basis for adding the other abbey buildings which must have been present.

It is also interesting to note that ‘wonky’ or misaligned naves can be seen in other examples, for instance Whitby abbey.