No.2 Gun emplacement, detail of calibrated ring and holdfast.

Description No.2 Gun emplacement, detail of calibrated ring and holdfast.

Date 24/5/1996

Collection Records of the Royal Commission on the Ancient and Historical Monuments of Scotland (RCAHMS), Edinbu

Catalogue Number C 73232 CN

Category Photographs and Off-line Digital Images

Copies SC 673072

Scope and Content Gun holdfast and graduated ring, World War II gun emplacement, Rerwick Head Battery, Mainland, Orkney Islands In both World Wars coast batteries were built to protect the channels into Scapa Flow, the greatest concentrations of firepower being at the main north-western and southern entrances to the Flow. In World War II there were also seven coast batteries on the east coast of Orkney Mainland protecting the approaches to Kirkwall Bay, which served as an examination anchorage where foreign shipping was impounded and searched for contraband. These batteries formed the Kirkwall Fire Command centred on Rerwick Head Battery, which also included a shore station for a controlled minefield in Shapinsay Sound. This view within the front area of one of the two six-inch gun emplacements shows the well-preserved remains of the steel bolt ring and concrete base, or holdfast, on which the gun was actually mounted. For operational stability the holdfast was set and bolted into a deep concrete substructure, and is here surrounded by a graduated or calibrated ring which provides 360-degree directional bearings, a useful feature which is peculiar to a number of Orkney coast batteries. At the heart of the Orkney archipelago, Scapa Flow was the main fleet anchorage for the Royal Navy during both World Wars. Its vital importance led to the creation of one of the most concentrated defence networks in Britain. Source: RCAHMS contribution to SCRAN.

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