The Governor, General Elliot (later called Baron Heathfield of Gibraltar) is said to have 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 'Notch'.

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. Permission was granted, and Ince started work under the direction of Lieutenant J Eveliegh, a Royal Engineer, Aide de Camp to the Governor, on May 25th, 1782.

At the end of the Great Siege in 1783, the defeated Commander of the French and Spanish troops, the Duc de Crillon, on being shown the fortifications that had led to the defeat of his troops commented, "These works are worthy of the Romans". This comment highlights the ingenuity of those men who against all odds endured the onslaught of the advancing forces and were still able to devise a unique system of defence which afforded them victory.