The History Channel was at the Royal Armouries' Portsmouth outpost at Fort Nelson last week to capture uniformed gunners from the Portsdown Artillery Volunteers firing a World War Two mobile Three-Seven anti-aircraft (AA) gun.
The poignant reminder of Portsmouth's suffering during the Blitz evoked powerful memories of the Victorian building’s role during the Second World War, when a battery was sited outside the Fort at Monument Farm.
At the height of the bombings the city came under repeated attack from the Luftwaffe, and the 3.7 gun was the main line of defence.
"It was our answer to the German 88 – but better," explained The Armouries' Keeper of Artillery Nick Hall. "More than 2,000 were built and it fired more rounds in a minute and to a higher 'ceiling' of about 32,000 feet."
Sadly, unlike the 88 millimetre, the 3.7 was only rarely converted to a ground anti-tank and artillery role, and therefore didn't cause as much damage as its German counterpart.
More usually the mobile guns were attached to a field army to give anti-aircraft defence. After their role as Blitz and coastal defence they went on to serve widely overseas during WWII campaigns in North Africa, Italy and the Mediterranean, and in Northern Europe from D-Day onwards.
Part of the National Collection of more than 350 historic cannon and big guns held at Fort Nelson, the 3.7 was acquired about 20 years ago and has been dismantled and extensively restored. It will eventually take pride of place in a breathtaking glass-fronted new gallery, which is currently under construction at the Portsdown Hill Fort.