St Nicholas Church
St Nicholas Church site is in close proximity to the assumed position of St Nicholas Church (Gardner 1754 records it as lying 20 rods (100m) SE of Blackfriars Monastery). The debris field lies 168m SSE of Blackfriars ruins in the scoured area of seabed east of the inner sand bank. The ruins appear as scattered blocks of masonry in the multibeam images lying in an area of the sea floor that is lower than the surrounding bed. The site lies some 410 m east from the present (2012 AD) cliff line, at a depth of 8.4 metres and covers an area of approximately 630 m2. The debris field is symmetrical with no clear western accumulation of larger blocks. This is in accordance with the description of the church as a cruciform structure with a central tower. St Nicholas church is reported to have probably collapsed over the cliffs sometime in the late 15th Century (c.1480 A.D. Gardner 1754) which would give the ruins an approximate time of submergence under the sea of 529 years. However, the reconstruction of cliff retreat, coupled with the position of the ruins, supports the view that the ruins have been on the seabed since c. 1700, which reduces the period of submergence to 332-360 years; a similar time to the ruins of St Peter's. The church was ruined and stripped of the most valuable materials (wood, lead, bells). Thus the remains are those of a ruined structure that collapsed down a cliff (height of cliff c. 19m based on reconstructed topography). The lack of a building on this area on the Agas map may point to it being nothing more than the foundations of the former church.
Diver surveys were conducted at this site in 2008 and resulted in recovery of four stones that were adjacent to larger structural blocks. Two of these stones contained traces of lime mortar adhered to their surface. Blind analysis of a sample of this mortar and a sample of mortar recovered from inside a collapsed section of the southern wall of Greyfriars monastery, was undertaken for English Heritage by Sandberg LLP (report 39360/C). This confirmed the sample recovered from the submerged site as of identical composition to that of the Greyfriars monastery sample. Diver surveys undertaken in 2008 in poor visibility confirmed the presence of relatively large blocks of flint and rubble scattered over the site, and the possible presence of some worked stone material. The diver survey also provided independent estimates of the block sizes as approximately 1.4m length and between 03-0.6m height above seabed. The Klein 3900 sidescan survey in 2009 (Figure 27), gave an average block size of 1.3m length by 0.90m width, whereas the higher resolution MBES survey of 2012 record them as larger at 1.72 x 1.10m as a result of the burial of the smaller blocks visible in the earlier survey. The 2008 and 2012 multibeam surveys give a block height above seabed of between 0.3-0.8m, similar to those reported at the St Peter's and All Saints sites (Bacon & Bacon 1979; 1988).