The Great Siege Tunnels were in a state of transition at the time of my visit. They appear to be removing the set tableaux depicting scenes from the times, and replacing them with display boards and some sort of audio commentary system. Only time will tell if it is an improvement.
During the Great Siege of 1779-1783 the Governor, General Elliot, a offered a reward to anyone who could tell him how to get guns onto a projection from the precipitous northern face of the Rock known as The Notch, so that they could fire down on the besieging troops.
A Cornishman, Sergeant Major Ince, a member of the Company of Soldier Artificers (forerunners of the Royal Engineers), suggested that this could be done by tunnelling through the rock, and work on the tunnel commenced in 1782.
In order to provide ventilation and to aid the quick disposal of the waste, openings were cut in the side of the cliff. It was soon realised that these openings would make excellent gun embrasures and cannon were mounted behind them without waiting to get to the Notch. In fact so effective were they, that the siege ended before the Notch was reach.
Tunnelling continued, but in order to provide protection for the guns, it was decided to mount them in a chamber inside the promontory rather than out in the open. This is now known as the St George's Hall.
Sergeant Major Ince was given a Commission and granted a plot of land on the Upper Rock still known as Ince's Farm. In addition, the Duke of Kent (Gibraltar's Royal Governor) presented him with a valuable horse. Quite what Ince made of the horse isn't recorded.