This is the slightly more detailed and careful of two identical views in this sketchbook; the other very quick sketch faces it on folio 61 (D10514; Turner Bequest CXL 54). The subject is definitely Camber Castle, as also suggested by Finberg, rather than a Martello tower. This is the central block seen from inside the walls; these can just be made out to left of centre. In the present sketch, Rye appears in the distance. There is a view of the castle from the surrounding levels on folio 62 (D10516; Turner Bequest CXL 55).