Fortifications of Gibraltar
The Gibraltar peninsula, located at the far southern end of Iberia, has great strategic importance as a result of its position by the Strait of Gibraltar where the Mediterranean Sea meets the Atlantic Ocean. It has repeatedly been contested between European and North African powers and has endured fourteen sieges since it was first settled in the 11th century. The peninsula's occupants – Moors, Spanish, and British – have built successive layers of fortifications and defences including walls, bastions, casemates, gun batteries, magazines, tunnels and galleries. At their peak in 1865, the fortifications housed around 681 guns mounted in 110 batteries and positions, guarding all land and sea approaches to Gibraltar. The fortifications continued to be in military use until as late as the 1970s and by the time tunnelling ceased in the late 1960s, over of galleries had been dug in an area of only.
Gibraltar's fortifications are clustered in three main areas. The densest fortifications are in the area where historically Gibraltar was under the most threat – at the north end of the peninsula, the North Front, facing the isthmus with Spain. Another group of fortifications guards the town and the harbour, referred to as the West Side. The southern end of the town is guarded by the South Land Front. Few fortifications exist on the east side, as the sheer cliff of the Rock of Gibraltar is a virtually impassable obstacle. Further fortifications occupy the plateaus of Windmill Hill and Europa Point at the southern end of the peninsula. Lookout posts and batteries on the summits of the Rock provide a 360° view across the Strait and far into Spain. Although Gibraltar is now largely demilitarised, many of the fortifications are still intact and some, such as the Great Siege Tunnels and the Charles V Wall – where many of Gibraltar's population of Barbary macaques live – have become tourist attractions.
Topography
The nature and position of Gibraltar's defences have been dictated by the territory's topography. It is a long, narrow peninsula measuring by wide at maximum, with a land area of about. The only land access to the peninsula is via a sandy isthmus, only above sea level, most of which is now occupied by the Spanish town of La Línea de la Concepción. The peninsula is dominated by the limestone massif of the Rock of Gibraltar, which presents a sheer cliff over high at its north end, facing the isthmus. The Rock extends southwards for with several peaks before it descends to two southern plateaus at heights of between and above sea level. The southern tip of Gibraltar is surrounded by steep cliffs. The Rock itself is asymmetric, with a moderate slope on the west side and a very steep slope on the east side. The original core of the town of Gibraltar occupies the lower north-west side of the Rock, adjoining the Bay of Gibraltar, though it has grown considerably to the point that the built-up area now stretches all the way to Europa Point on the southern tip of the peninsula. A great deal of 20th century land reclamation on the west side has also widened the coastal area, which was formerly quite narrow. A couple of small settlements, originally fishing villages, occupy the east side.These features have made Gibraltar a naturally strong defensive position. The isthmus lacks any natural cover, exposing any approaching enemy to opposing fire. The heights of the Rock form a natural barrier to movement and rocky ledges provide natural platforms for gun batteries. The sheer cliffs on the north and east sides of the Rock block access from those directions and the sea cliffs around the southern end of the peninsula make landings there difficult, especially if opposed. A single road connects Gibraltar with Spain, and within the territory most roads are narrow and often steep due to the restricted land area. Over the centuries, Gibraltar's successive occupants have built an increasingly complex set of fortifications around, on top of and incorporating the territory's natural features.
Writing in 1610, the Spanish historian Fernando del Portillo commented that Gibraltar was "a stronghold from its very topography which with a little art could be made impregnable," and so it has proved. The Irish writer George Newenham Wright observed in 1840 that "the surface of the Rock is wholly occupied by defensive works; where it was possible, and often where it appeared almost impracticable, batteries and fortifications have been formed. From Europa Point, which pushes into the sea on the south side, to the highest point of the Rock, there is not a single point that has not been put into a defensible condition... Proceeding towards Europa Point, at the entrance of the town, fortifications, magazines, barracks, and batteries are placed wherever the nature of the surface would permit."
History
Moorish period
Gibraltar's fortifications have evolved in a number of stages. Its first permanent inhabitants, the Moors of North Africa, are said to have established a fort on Djebel Tarik "to be on guard and watch events on the other side of the Straits" as early as 1068. Gibraltar was fortified for the first time in 1160 by the Almohad Sultan Abd al-Mu'min in response to the coastal threat posed by the Christian kings of Aragon and Castile. The Rock of Gibraltar was renamed Jebel al-Fath, though this name did not persist, and a fortified town named Medinat al-Fath was laid out on the upper slopes of the Rock. It is unclear how much of Medinat al-Fath was actually built, as the surviving archaeological remains of Moorish Gibraltar are scanty. A portion of wall some long still survives to the south of the main part of the city of Gibraltar, of similar design to defensive walls in Morocco. It may have protected a settlement on the upper part of the Rock, around where the modern Queen's Road is, but firm archaeological evidence is lacking.The city fell to the Castilians in 1309 after the first siege of Gibraltar and its fortifications were repaired and improved by King Ferdinand IV of Castile, who ordered the construction of a keep above the town. The Castilians maintained control of Gibraltar until 1333, resisting a Moorish siege in 1315, but relinquished it in 1333 after the third siege of Gibraltar. After defeating a Castilian counter-siege which ended after two months, the Marinid sultan Abu al-Hasan Ali ibn Othman ordered a refortification of Gibraltar "with strong walls as a halo surrounds the crescent moon". Many details of the rebuilt city are known due to the work of Abu al-Hasan's biographer, Ibn Marzuq, whose Musnad describes the reconstruction of Gibraltar. The city was expanded, and a new defensive wall was built to cover the western and southern flanks, with towers and connecting passages added to strengthen them. The existing fortifications were also strengthened and repaired. The weak points that the Castilians had exploited were improved.
The refortified city occupied the north-eastern part of the present-day city, reaching from the area of Grand Casemates Square up to Upper Castle Road. It was divided into three main quarters which functioned as a series of baileys through which troops could fall back in stages. The Tower of Homage was located at the highest point, serving as a final redoubt. The Tower was a formidable square keep situated within a kasbah and had the largest footprint of all the towers to be built in Moorish Al-Andalus. It was a much-strengthened rebuilding of an earlier tower and still bears scars on its eastern wall from projectiles shot by the Castilians during the siege of 1333. The kasbah could only be accessed via a single gate, which still survives; an inscription visible up to the 18th century recorded that it had been dedicated to Yusuf I, Sultan of Granada.
Below the kasbah was an area later called the Villa Vieja by the Spanish, accessed via the Bab el-Granada, and below that was a port area called La Barcina by the Spanish, which may have taken its name from the Galley House built there by the Moors. It had three separate access gates: the Land Gate, the Sea Gate and a southern gate, the Barcina Gate. The core of the city was surrounded by substantial defensive walls with tall towers topped by merlons. Other than the Tower of Homage, two such towers still survive; one square based which was fitted with a clock in Victorian times and another constructed en bec. The walls were at first built using tapia, a lime-based mortar made with the local sand and faced with decorative brickwork to simulate masonry. The builders later changed their construction methods to utilise stone interlaced with brick, a rather stronger structure. The southern flank of the walls has survived relatively intact, and vestiges of the other walls are most likely still to be found underlying the modern defensive walls constructed by the British. To the south of the fortified city was an urban area known as the Turba al Hamra, literally the "red sands", named after the predominant colouration of the soil in that area. Ibn Battuta visited the city in 1353–54 and wrote:
Spanish period
Castile regained control of Gibraltar in the Eighth Siege of 1462. The Moorish threat receded following the completion of the Reconquista and the fortifications were allowed to fall into decay, with very few cannon mounted on the batteries. In 1535, the Spanish naval commander Álvaro de Bazán the Elder warned King Charles I that Gibraltar's defences were seriously inadequate and recommended that the Line Wall Curtain be extended all the way to Europa Point on the southern tip of Gibraltar and that the town's southern wall should be strengthened. However, his advice was ignored. The soldier and writer Pedro Barrantes Maldonaldo noted that by 1540 Gibraltar's north-west bastion had only four guns, while the castle's few guns were all dismounted, and there were no gunners. The garrison's equipment was antiquated and their numbers were few. The town's walls were still essentially medieval and could not have resisted mid-16th century artillery. The fall of Constantinople 90 years earlier showed just how vulnerable such walls could be in the face of a heavy artillery bombardment.The town's inhabitants paid the price for this neglect in September 1540 when Barbary pirates from North Africa carried out a major raid, taking advantage of the weak defenses. Hundreds of Gibraltar's residents were taken as hostages or slaves. The Spanish crown responded to Gibraltar's vulnerability by building the Charles V Wall to control the southern flank of the Rock. The wall's builder, the Italian engineer Giovanni Battista Calvi, also strengthened the Landport Gate. Another Italian engineer, Giovan Giacomo Paleari Fratino, extended the wall onto the Upper Rock at some point probably between 1558 and 1565. A lookout tower, one of several constructed along Spain's southern coast during this period, was built at the eastern end of the isthmus linking Gibraltar with the Spanish mainland. This structure, known as Devil's Tower, was demolished during World War II. The German engineer Daniel Specklin is also thought to have been employed in improving Gibraltar's fortifications between 1550 and 1552. Although there is no direct evidence, the Spanish fortifications at the southern end of the town are virtually identical in design to drawings in Specklin's posthumously published Architectura von Vestungen and on this basis it has been suggested that he was the designer of Gibraltar's southern works.
Although the 16th century works improved Gibraltar's defences significantly, they still had major shortcomings. Fernandez del Portillo noted in 1610 that while Gibraltar was "girt by quite a good wall with bastions at corners", there still remained work to be done to complete the fortification plans that had been drawn up in the previous century. He felt that "perhaps what does exist is enough to withstand an assault and more." The biggest weakness was the lack of an effective sea wall to resist naval bombardments, and in 1618 Philip III of Spain authorised works to create a new mole for a deep-water harbour, protected by a newly constructed gun platform and the Torre del Tuerto fort. Philip IV subsequently ordered a major modernisation of Gibraltar's fortifications due to hostile activity in the Strait by the Protestant powers of northern Europe – particularly England and the Dutch Republic. On visiting Gibraltar in 1624, the king found that his carriage could not fit through the Landport Gate. He had to walk into the town instead and expressed his displeasure, to which Gibraltar's military governor is said to have retorted: "Sir, the Gate was not made for the passage of carriages, but for the exclusion of enemies."
The fortifications had only relatively thin crenelated walls, which were insufficiently strong to counter artillery bombardments. They were lined with many tall towers for archers, but could not be used to mount cannon. Don Luis Bravo de Acuña, the governor of Gibraltar, produced a report for the king recommending a series of changes to the territory's fortifications. A series of new batteries was built along the Line Wall, each named after saints, and a New Mole was built to provide additional protection to ships in the harbour. On the north side of Gibraltar, the Muralla de San Bernando was fully adapted to mount cannon facing the isthmus with the old archery towers being pulled down and replaced by bastions. The Old Mole, stretching into the Bay of Gibraltar, provided further mountings for cannon to sweep the isthmus. A series of defensive works constructed on a glacis above the entrance to the town provided further enfilading fire. A formidable bastion was constructed to protect the south of the town; known as the Baluarte de Nuestra Señora del Rosario, and now as the South Bastion, it enfiladed the ditch across the Gate of Africa, now the Southport Gates. However, the effectiveness of the new fortifications was undermined by the continued failure of the Spanish crown to provide enough troops to man them.
In August 1704, an Anglo-Dutch invasion force sailed into the Bay of Gibraltar and rapidly overcame the poorly manned garrison. Don Diego de Salinas, the last Spanish governor of Gibraltar, had repeatedly called for the garrison and fortifications to be strengthened, but to no avail. When Admiral George Rooke's fleet carried out the capture of Gibraltar, his 350 guns were opposed by only 80 iron and 32 brass cannon of various calibres in Gibraltar. Most of the Spanish guns were not even manned. De Salinas only had about 150 regular soldiers, very few of whom were gunners, and about 250 armed civilians. Gibraltar fell after only four days of fighting. A Franco-Spanish army laid siege shortly afterwards and was able to inflict substantial damage on the old Spanish fortifications, which crumbled under the constant pounding. However, the Anglo-Dutch garrison was able to repair the worst of the damage and repelled Franco-Spanish attacks while being resupplied and reinforced by sea. After eight months the French and Spanish abandoned the twelfth siege of Gibraltar.