This multi purpose gun was part of the rock defences during the ww2 era and would have had a general role..i presume it was also placed near the entrance to rosia road tunnel to protect the road area in case of enemy advancing by road..This gun was mostly used for coastal defence but could be used for other purposes..It fired a 6 pounder shell.,it wasusually manned by 2 or 3 people..there are also several searchlights emplacements in the vicinity and a bunker used by the crew of the battery.<br>
This appears to be a <a href="https://en.wikipedia.org/wiki/Ordnance_QF_6-pounder" class="extiw" title="en:Ordnance QF 6-pounder">6-pounder anti-tank gun</a>.
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