NHER 2187 (Monument record) - The Sea Bank

Formerly called Roman Bank. Of Late Saxon - medieval date.
1984. Roman coin found in bank at Terrington.
1985. Medieval and Middle Saxon and Late Saxon sherds from bank.
1992. Excavation across bank produced 11th/12th century sherds.

July 1993. Excavation.
Excavation of section across Sea Bank near Islington Hall Farm, Tilney All Saints.
This work indicated that the bank had been constructed on the boundary between the lower salt marsh and the mud flat. A fragment of brick was recovered towards the base of the bank.
See interim report (S1) for further details. The results of this work are also summarised in (S12).
Amended by P. Watkins (HES), 13 March 2017.

22 July 1993. NLA aerial photography.
Bank visible in undergrowth.
Excavation by JCB taking place at one end (north) of the upstanding length.
M. Brennand (NLA) 7 February 2001.

January 1995. Watching Brief.
Observation of a cutting through an upstanding part of the Sea Bank at Islington, Tilney All Saints (Context 14).
See report (S2) for further details. The results of this work are also summarised in (S13).
P. Watkins (HES), 13 March 2017.

December 1997-January 1998. Watching Brief.
Monitoring of groundworks associated with construction of new road to east of Jubilee Bank Road (TF 6037 2007), which follows the line of the Sea Bank. No features or deposits of archaeological significance observed and no finds recovered.
See report (S10) for further details.
P. Watkins (HES), 10 February 2014.

April-June 1998. Watching Brief.
King's Lynn to Sutton Bridge Trunk Water Main (Plots 4 and 29/30).
Observation of works for laying of pipeline.
At TF 5805 1920 (Plot 4):
Bank already cut away (for railway construction?) and standing elements not affected further by pipeline.
At TF 5088 1965 (Plot 29/30):
Pipeline moled through bank.
See report (S11) for further details.
The archive associated with this work has been deposited with the Norwich Castle Museum (NWHCM : 2016.38 and NWHCM : 2017.417).
P. Watkins (HES), 18 March 2015. Amended 17 May 2019.

October 2002. Norfolk NMP.
It is presumed that the mapped feature represents the course of the bank, but it may have undergone substantial alteration since its original construction. There are several areas where the feature recorded as NHER 2187 may in fact be pre-dated by an earlier bank feature.
The course of the bank that runs along the Clenchwarton/King’s Lynn parish boundary now lies under a road, which may have been partially raised when the road was constructed (S3).
The bank enters map square TF62SW at TF 6000 2272, from where it runs due eastwards to the edge of the Great Ouse Lynn Channel (NHER 13532), constructed in the first half of the 19th century. A section has presumably been truncated by the channel. The bank then runs due southwards in a slightly irregular line, and exits the map square at TF 6027 2000. This stretch of bank forms the parish boundary between Clenchwarton and King’s Lynn. There are drains running down each side of the bank although, it is not certain whether theses are original ditches or more modern features. There is a length of ditch on the eastern side of the bank running from TF 6014 2171 to TF 6016 2197, which is substantially wider than the drains, and is more likely to be a ditch associated with the banks construction. The bank appears to post-date and incorporate saltern mounds NHER 27946 at TF 6013 2155.
The course of the bank then turns to the west and enters map square TF 52 SE at TF 6000 2271 (S7). The bank runs approximately south-westwards on an irregular, meandering (almost higgledy-piggledy) course for a length of approximately 3.25 km (S8), before turning to the west at TF 5740 2096. There are intermittent ditches on both the northern and southern sides of this length of the bank, although it is unclear whether they are on the line of original features or simply later drains. The southern section of this stretch operates as the parish boundary between Clenchwarton and Terrington St Clement.
The bank is visible as an approximately east to west aligned earthwork in 1946 (S4) running from TF 5740 2096 to TF 5661 2103. This once well preserved stretch has a meandering appearance with two northern protrusions or bulges in the course of the feature, which are the alleged sites of former breaches in the bank (S6). This stretch of the bank is now ploughed flat.
There is an approximately 800m break in the discernible line of the bank within the area of Little London. It is almost certain that the bank was present within this area, or there would be an obvious flood risk to the unprotected area, although no trace of the bank is now visible. It is probable that the line of the bank ran to the north of rather than under the road known as Northgate Way.
The probable course of the bank is again visible as a (probably truncated) earthwork (S4) for a length of 215m from TF 5581 2111 to 5563 2123, before it appears as a distinctive light coloured cropmark from TF 5549 2126 TF 5519 2137 (S4). This levelled stretch was recorded as an earthwork at the turn of the last century (S5). From this point westwards the bank is again situated beneath a road (New Roman Bank).
M. Brennand (NMP) 24 October 2002.

August 2007. Survey.
The slight remains of two banks are present, both nearly flattened and widely spread. They stand along the west and south edges of a long, narrow field which is still defined by the dykes that ran alongside the main bank. To the immediate south a small plantation obscures another part of the sea bank which lies flattened in this area.
See (S9) for further details.
A. Cattermole (NLA), 24 September 2007.

August 2018. Watching Brief.
Monitoring of excavation of seven geotechnical test pits on or close to the line of the Sea Bank at Wiggenhall St Germans (along proposed line of haul road between TF 5837 1517 and TF 5889 1489).
These all revealed a similar sequence of sandy silt alluvium, subsoil and topsoil. No deposits or other remains associated with the Sea Bank were identified.
Information from report uploaded to OASIS. HER copy awaited.
An archive associated with this work has been deposited with Norwich Castle Museum (NWHCM : 2019.84).
P. Watkins (HES), 13 February 2025.