THE GREAT SEIGE TUNNELS
When visiting Gibraltar it really is worthwhile visiting the Great Seige Tunnels. They were carved out by merchant marines in order to defend Gibraltar during The Great Seige 1779-1783.
During the war of independance when Britain was busy on the other side of the pond, the Spanish and French used this to their advantage and advanced in order to take over the rock. For 4 long years the rock was under attack and at one point in 1782 the troops got very close. The batteries could not fire on them due to the awkward angle that they were advancing.
General Elliot, the then governor offered a reward for anyone who could figure out a way to get the cannons onto the north face of the rock (the notch) in order to prevent the attack.
Sergeant Major Ince was the person that cme up with the idea that it was possible to tunnel through the rock to get to the north side. Permission was granted. He was later rewarded a commission and an area of land on the upper rock, known as Ince’s farm.
Work commenced on the tunnels in may 1782 and although the men had only sledge hammers, metal bars and gunpowder to work with in just 5 weeks 18 men had driven a tunnel 8 sq feet by 82 foot. They were using brute force and inferior tools and as the work progressed the fumes were so bad from the gun powder it was decided to open a vent to let in some fresh air to stop the men from suffocating.
It was then realized what an excellent embrasure this would make for a cannon. The tunnel was driven into a hugh chamber (St George’s Hall), where a battery of 7 cannon were installed. A wet cloth was hung from the rods above the cannons to stop sparks ingniting the remaining gunpowder.
The cannons were mounted in the tunnels and holes were cut out into the rock all alone the face of the side facing the mainland. This was a far better plan that the original idea of having a tunnel in order to move the cannons about.
At the end of The Great Siege the defeated commander of the French and Spanish troops, The Duc de Crillon, was shown the fortification that led to his demise and remarked that these works were worthy of the Romans.
When you visit Gibraltar if you look closely you can see the holes in the rocks face.
By the end of the second world war the 82 ft tunnel was extended to 30 miles of tunnel traversing throughout the rock. The use of diamond drills and more modern tunneling techniques enabled this.