1- THE FORTRESS OF ISABEL II

The Fortress of Isabel II was built between the years 1850 and 1875; it is located in one of the most beautiful spots on the island of Minorca, constituting one of the best examples of late 19th Century military architecture. Its strategic position above Mahon harbour mouth made it one of the key points in the island’s defence system. At present La Mola represents a valuable Historical Military Heritage, set in a natural environment of prime importance.

 

2- FRONTS 9-10

The tenaille fortification (literally meaning pincers) cuts the Mola peninsula in two by means of a deep dry moat, from the north coast to the Clot de La Mola; it consists of a series of salients and recesses (numbered from 0-9) which form the fore-mentioned “pincers”.

Along the whole of the 9th and 10th front, which covers the harbour entrance, we can observe from the cannon emplacements the walkway in the counter-escarpment, with three steps and a parapet ending in a small quarter-circle parade ground. The fusiliers undertook the close defence of the fortress from this walkway before withdrawing via the Queen’s Gate.

Inside, there is a continuous gallery with a series of beautiful vaults. These are called casemates and protect the cannon embrasures. This front ends in the parade ground above Cala Del Clot, whose battery emplacements were destroyed by strong gales.






3 - UNDERGROUND GALLERIES (THE MINE)

Under the area of the 8th, 9th and 10th front a labyrinth of underground galleries known as The Mine can be found. Here there are a large number of gunpowder magazines, workshops and stores. The ammunition was hauled up shafts with the aid of a pulley, to supply the casemated cannons in the galleries above.

At the end of The Mine, turning left, is the intermediate firing order which defends the moat in order to flank the Queen’s Gate. Here the loop-holes are cut specifically at different angles; this enables the riflemen to cover the whole moat area, as well as letting natural light into the gallery.

Turning back, out of the gallery and up the ramp the upper loop-holed firing order can be seen, above the gallery just visited.

4 - THE QUEEN’S GATE

The Queen’s Gate is the entrance to the fortress. Within the gate is a control point and guard house. Being the main entrance it is well protected,

from both remote and close attack. Covering the intermediate defence, to the front of the Queen’s Gate, is the counterguard, a defensive work founded on artillery emplacements; the close defence is undertaken by fusiliers from a series of galleries with loop-holes (vertical firing slits).

The inauguration of the fortress took place in 1852, and in honour of the Queen was named the Fortress of Isabel II. The plaque over the gate commemorates this day.

On the occasion of Queen Isabel II of Spain’s visit in 1860, a second inauguration took place. The following years saw an important increase in the work force and finances which allowed the fortress to be finished.






5 - THE HORNWORKS

Passing through a redoubt (stronghold), a construction with two firing orders and surrounded by a moat known as the Cutting (the second front), we enter into the Hornworks for the defence to the forefront of the fortified line.

The redoubt is a separate building designed for the withdrawal of defending troops should the Hornworks be taken by enemy.

The Hornworks itself is the first line of defence against a land attack. It contains two wings of casemated galleries, to the right these defend the north coast and to the left the port.

The head of the Hornworks has two firing orders: one of which is casemated with 18 cannon emplacements and the upper one in barbette (firing over the parapet without an embrasure) for 8 artillery pieces.

The Hornworks has a total of 54 cannon emplacements.







6 - THE HORNWORKS REDOUBT

In fortification terms a cutting means a second front. This was the purpose of this magnificent group of buildings, if the enemy were to take the Hornworks. It has three firing orders for fusiliers and light shrapnel cannons, with which they could enfilade the rear of the Hornworks, including the interior of the lateral galleries, and their gun embrasures. This redoubt is separated from the surrounding areas by a moat, and is reached via two bridges, which should have been retracting. The redoubt in the cutting corresponds to Montalembert’s so–called third or circular system. The trace is known as “swallowtail”.








7 - THE COOP WITHIN THE HORNWORKS

Jutting out from the head of the Hornworks is the Coop, a defensive element in order to flank or fire along the length of the moat.

Down the ramp, inside the coop, leading down to the lower floor and moat, there is a spiral staircase, which is a magnificent piece of stonemasonry. The Coop consists of two firing orders for both fusiliers and artillery.

Returning up the ramp, a series of steeply inclined loop-holes can be seen on both sides of the upper gallery, for firing at enemy should they enter the Coop.



8 – RESERVOIR AND DECANTING POOLS

On La Mola peninsula, the ground is on an inclination from North West to South East and the geological strata are distributed on a slope. This means that the phreatic stratum, the subterranean water level, found where the limestone and porous calcareous rocks meet with the impermeable sandstone and slate, is also on a slope. This geological characteristic forced the subterranean waters to flow out towards the exterior of the fortress, emerging in one single spring, in the Clot de la Mola.

This meant that the workforce had to install a series of channels, reservoirs and water cisterns, in order to collect rainwater and supply the garrison with drinking water. Likewise the decanting pools, on different levels progressively eliminate any dirt and debris in the water, so that it flows into the cisterns as clean as possible.

9 - RECESS 5

The area known as Recess 5 is made up of a tenaille, or pincer, designed to trap the attacking enemy in cross-fire.

To the rear the descent to the intermediate and lower firing orders is via a very steep ramp. The passage leading to the lower orders and Recess 5 moat, via a postern gate, is protected by a platform above the gate and a series of highly placed loop-holes, reached from within the intermediate and upper galleries.

The defence to the front of Recess 5, is undertaken by three firing orders on one side and four on the other which cross-fire.






10 - RECESS 5 MOAT

The postern gate, leads to the moat which widens here to hold the redoubt. This redoubt has three firing orders: the upper one is casemated for cannon and the lower loop-holed for fusiliers. Looking up to the left of the redoubt a magnificent gargoyle can be seen and entering inside a beautifully proportioned elliptical vent.

On returning to the postern gate, looking back towards the escarpment (the walls of the fortification) the Recess 5 firing orders can be seen which cross-fire. The upper cannon embrasures took care of long distance defence and the lower loop-holes defended the moat and the walkway.

11 - THE LOOP-HOLED GALLERY

The Loop-Holed Gallery is a front for fusiliers uniting Recess 5 with Salient 3 within the escarpment wall. It is 390 metres long and has 48 perfectly aligned casemates, the majority of which each have two loop-holes and a smoke vent. The loop-holes are at an inclined angle ideal for firing down into the moat and onto the walkway.

Above the Loop-Holed Gallery, corresponding to the 3rd and 4th front, there is a parapet and emplacements for large artillery pieces in barbette, known as the Batería de la Princesa (Princess Battery).

12 - THE PRINCESS TOWER ( OR ERSKINE TOWER AS NAMED BY THE ENGLISH)

The Princess Tower belongs to a period prior to the fortification. It was built by the British in their last dominion of the island (1798-1802). Prior to the construction of the Fortress of Isabel II, it formed part of the precarious defence system. The system was made up of a series of defence towers around the island’s coastline. Called Martello towers by the English, as a similar construction above Martello Bay in Corsica successfully resisted attack by a British frigate; these towers were then included in their tactics for coastal defence.

In 1958 this tower, converted into a gunpowder magazine, was destroyed when struck by lightning. The ruins of the tower indicate the violence of the explosion, blowing out whole sections of the walls.

13 – THE QUEEN’S WATER CISTERN


In order to provide water for the troops defending the Fortress of Isabel II, it was necessary to devise this system for collection of rain water-The Queen’s Water Cistern. It is excavated out of the limestone and is reached by descending some narrow steps also cut out of the rock. It has a recess in the bottom acting as a sediment pool, for collecting dirt. The cistern was filled through an orifice on one side of the vaulted roof and extracted through another in its centre which also aided illumination.

It is said that Isabel II bathed here during her visit in 1860, and as such is sometimes called “The Queen’s Bath or Pool”, however this was highly unlikely given the nature of the surroundings, which make one suspect that this was merely an unfounded rumour.

14 - THE PRISON AND OTHER BUILDINGS


By the side of the panel, the visitor will find the building which was formerly the prison. This establishment was used as a military prison from 1948 until the 1970s. Prior to this, the prison enclosure had been set up in two pavilions on the far side of the parade ground.

The fortress having lost its defensive use over the years, although still acting as a deterrent as well as a military prison, was used as a training camp for recruits, with a permanent garrison in the 381mm battery, the Infantry barracks (high) and the Artillery barracks (low).

Continuing past the second prison and following the track you will be able to see the Queen’s Powder Magazine built in 1852, prior to her visit; a one storey building, surrounded by a wall to contain a possible explosion.

15 – GEOLOGICAL ASPECTS

The area where the huts belonging to the garrison from the 381mm battery are, is in reality one of the quarries which was opened up in La Mola to extract by traditional Minorcan means the blocks of stone which built part of the Fortress of Isabel II. Others came from the ruins of the demolished Fortress of Saint Philips, on the other side of the harbour; they stand out due to their darker and more eroded appearance.



16 - THE 15 INCH (381MM) VICKERS BATTERY

Towards the end of Alfonso XIII’s reign, Spain ordered eighteen 15” Mark II Cannons from the English company Vickers. Six of these pieces were destined for Minorca; two were installed in La Mola during Spain’s Second Republic, they finished mounting the second piece in this battery during the first year of the Civil War (1936).

Designed as naval cannons, these large bore pieces were installed on the coastal cliffs, as there were no ships adequate for such large guns.

On this cliff top, more than 70 metres above sea level, the cannon’s turret with the 17.6 metre barrel weighing 88 tons, could gyrate 270º.

The three Vickers batteries located around the Minorcan coast covered almost three quarters of the coastline between them.

These cannons were so powerful that they were able to reach their objective at a distance of 35km, although in reality they were never fired in anger, only for instruction. They were able to perforate battle cruisers with 36cm of armour-plate at a distance of 23 km.
In order to hit their target they had a Firing Reference Point located near the guns with a Vickers Range-finder which calculated the target’s distance and future position.

The small but strategically important island of Minorca was so heavily defended that since the construction of the fortress and coastal batteries it never suffered a land attack.

This cannon was last fired in 1991.