The Tunstall pillbox, coordinates TA 31192 31960, was erected during WWII.
A mark made while the finishing cement was still wet gave the wording, 'C. NELSON HULL', but there was no date. (It is common to find such inscriptions on military structures along the coast.)
The pillbox is entered as RO46 in the English Heritage Rapid Coastal Zone Assessment Survey. RO refers to the civil parish of Roos in the East Riding of Yorkshire, which includes the village of Tunstall. Pillbox RO46 fell over the receding cliff to be in pieces late 2023.
Sharing the same coordinates but having the English Heritage reference RO55, a Royal Observer Corps (ROC) `Orlit’ structure, Type A, was mounted on top of the pillbox in 1951. This was the era of the Cold War. Type A referred essentially to ground or near-ground level installations, as apart from Type B, which were mounted on legs. Orlit Ltd, a construction company specialising in concrete builds, including 'prefabs', or prefabricated housing, ceased to exist when its post-war purpose became redundant. The Orlit was designated Post 18/K.1.
At the end of the same decade, Tunstall was chosen by the ROC as a site for an underground monitoring post, designed to continue functioning in the event of enemy attack. It operated from February 1959 as Master Post 20/T.1 (‘Master’ meant that other posts were controlled from the position) and closed in October 1968, to open once again in 1975 as Post 20/M.2, and be employed until 1991. Listed with the Orlit post as RO55 in the English Heritage catalogue, the bunker was sunk adjacent to the pillbox, which subsequently served as a restroom.
To estimate how far the bunker was from the cliff when installed, the online erosion calculator may be used. The nearest monitoring point, Profile 81, intersects the cliff line 61.22 metres to the north of the site.
Cliff recession from 1959 to 2024, a period of 66 years, at Profile 81 is shown as 106.89 metres. The range represents data to spring 2025. Average annual loss over the period is 1.62 metres per year (106.89/66). A further year may be added to bring the estimate to early 2026. 106.89 + 1.62 = 108.51 metres (118.67 yards).