Rock of Gibraltar

Last updated

Rock of Gibraltar
Rock of Gibraltar northwest.jpg
Western face of the Rock of Gibraltar, in April 2006
Highest point
Elevation 426 m (1,398 ft)
Prominence 423 m (1,388 ft) [1]
Coordinates 36°07′28.1″N05°20′35.2″W / 36.124472°N 5.343111°W / 36.124472; -5.343111 Coordinates: 36°07′28.1″N05°20′35.2″W / 36.124472°N 5.343111°W / 36.124472; -5.343111 [2]
Geography
Gibraltar map-en-edit2.svg
Location of the Rock of Gibraltar's summit
Location Gibraltar
Parent range Betic Cordillera
Geology
Age of rock Jurassic
Climbing
Easiest route Gibraltar Cable Car, Road, Hike

The Rock of Gibraltar (from the Moorish Gibraltar name Jabel-al-Tariq) is a monolithic limestone promontory located in the British territory of Gibraltar, near the southwestern tip of Europe on the Iberian Peninsula. [3] It is 426 m (1,398 ft) high. Most of the Rock's upper area is covered by a nature reserve, which is home to around 300 Barbary macaques. These macaques, as well as a labyrinthine network of tunnels, attract many tourists each year.

Contents

The Rock of Gibraltar, one of the two traditional Pillars of Hercules, was known to the Romans as Mons Calpe, the other pillar being Mons Abyla or Jebel Musa on the African side of the Strait. According to ancient myths fostered by the Greeks and the Phoenicians, [3] and later perpetuated by the Romans, [4] the two points marked the limit to the known world; although the Phoenicians had actually sailed beyond this point into the Atlantic, both northward and southward. [4]

The Mediterranean Sea surrounds Gibraltar.

Geology

Levant cloud forming against the eastern cliffs of the Rock of Gibraltar Clouds covering the walls of Gibraltar Rock.jpg
Levant cloud forming against the eastern cliffs of the Rock of Gibraltar

The Rock of Gibraltar is a monolithic promontory. The Main Ridge has a sharp crest with peaks over 400 m above sea level, formed by Early Jurassic limestones and dolomites. [5] It is a deeply eroded and highly faulted limb of an overturned fold. The sedimentary strata composing the Rock of Gibraltar are overturned, with the oldest strata overlying the youngest strata. These strata are the Catalan Bay Shale Formation (youngest), Gibraltar Limestone, Little Bay Shale Formation (oldest), and Dockyard Shale Formation (age unknown). These strata are noticeably faulted and deformed. [6]

Predominantly of shale, the Catalan Bay Shale Formation also contains thick units composed of either brown calcareous sandstone, soft shaly sandstone interbedded with bluish-black limestone, and interlayered greenish-gray marls and dark gray cherts. The Catalan Bay Shale Formation contains unidentifiable echinoid spines and belemnite fragments and infrequent Early Jurassic (Middle Lias) ammonites. [6]

The Gibraltar limestone consists of greyish-white or pale-gray compact, and sometime finely crystalline, medium to thick bedded limestones and dolomites that locally contain chert seams. This formation comprises about three quarters of the Rock of Gibraltar. Geologists have found various poorly preserved and badly eroded and rolled marine fossils within it. The fossils found in the Gibraltar limestone include various brachiopods, corals, echinoid fragments, gastropods, pelecypods, and stromatolites. These fossils indicate an Early Jurassic age (Lower Lias) for the deposition of the Gibraltar limestone. [6]

The Little Bay and Dockyard shale formations form a very minor part of the Rock of Gibraltar. The Little Bay Shale Formation consists of dark bluish-gray, unfossiliferous shale, which is interbedded with thin layers of grit, mudstone, and limestone. It predates the Gibraltar limestone. The Dockyard Shale Formation is an undescribed variegated shale of unknown age that lies buried beneath the Gibraltar's dockyard and coastal protection structures. [6]

Although these geological formations were deposited during the early part of the Jurassic Period some 175-200million years ago, their current appearance is due to far more recent events of about 5 million years ago. When the African tectonic plate collided tightly with the Eurasian plate, the Mediterranean became a lake that, over the course of time, dried up during the Messinian salinity crisis. The Atlantic Ocean then broke through the Strait of Gibraltar, and the resultant flooding created the Mediterranean Sea. The Rock forms part of the Betic Cordillera, a mountain range that dominates southeastern Iberia. [6]

The sheer east side of the Rock of Gibraltar Gibraltar eastside.jpg
The sheer east side of the Rock of Gibraltar

Today, the Rock of Gibraltar forms a peninsula jutting out into the Strait of Gibraltar from the southern coast of Spain. The promontory is linked to the continent by means of a sandy tombolo with a maximum elevation of 3 m (9.8 ft). [7] To the north, the Rock rises vertically from sea level up to 411.5 m (1,350 ft) at Rock Gun Battery. The Rock's highest point stands 426 m (1,398 ft) near the south end above the strait at O'Hara's Battery. The Rock's central peak, Signal Hill and the top station of the Gibraltar Cable Car, stands at an elevation of 387 m (1,270 ft). The near-cliffs along the eastern side of the Rock drop down to a series of wind-blown sand slopes that date to the glaciations when sea levels were lower than today, and a sandy plain extended east from the base of the Rock. The western face, where the City of Gibraltar is located, is comparatively less steep.

Calcite, the mineral that makes up limestone, dissolves slowly in rainwater. Over time, this process can form caves. For this reason the Rock of Gibraltar contains over 100 caves. St. Michael's Cave, located halfway up the western slope of the Rock, is the most prominent and is a popular tourist attraction.

Fossils of Neanderthals have been found at several sites in Gibraltar. In 1848, a Neanderthal woman's skull was found at Forbes' Quarry, located on the north face of the Rock. However, its significance was not recognized until after the 1856 discovery of the type specimen in the Neander Valley. Excavations in Gorham's Cave, located near sea level on the eastern side of the Rock, found evidence it was used by Neanderthals, and plant and animal remains in the cave gave evidence of Neanderthals' highly varied diet. [8]

Fortification

The Moorish Castle View of Moorish Castle from Grand Battery.jpg
The Moorish Castle

Moorish Castle

The Moorish Castle is a relic of Moorish rule over Gibraltar, which lasted for 710 years. It was built in the year A.D. 711, when the Berber chieftain Tariq ibn-Ziyad first landed on the rock that still bears his name. The 17th-century Muslim historian Al-Maqqari wrote that upon landing, Tariq burned his ships.

The principal building that remains is the Tower of Homage, a massive building of brick and very hard concrete called tapia. The upper part of the tower housed the former occupants' living apartments and Moorish bath.

The Rock of Gibraltar's North Front cliff face from Bayside (c.1810) showing the embrasures in the Rock Rock of Gibraltar 1810.jpg
The Rock of Gibraltar's North Front cliff face from Bayside (c.1810) showing the embrasures in the Rock

Galleries

A unique feature of the Rock is its system of underground passages, known as the Galleries or the Great Siege Tunnels.

The first of these was dug towards the end of the Great Siege of Gibraltar, which lasted from 1779 to 1783. General Elliot, afterwards Lord Heathfield, who commanded the garrison throughout the siege, was anxious to bring flanking fire on the Spanish batteries in the plain below the North face of the Rock. On the suggestion of Sergeant-Major Henry Ince of the Royal Engineers, he had a tunnel bored from a point above Willis's Battery to communicate with the Notch, a natural projection from the North face. The plan was to mount a battery there. There was no intention at first of making embrasures in this tunnel, but an opening was found necessary for ventilation; as soon as it had been made a gun was mounted in it. By the end of the siege, the British had constructed six such embrasures, and mounted four guns.

The Galleries, which tourists may visit, were a later development of the same idea and were finished in 1797. They consist of a whole system of halls, embrasures, and passages, of a total length of nearly 304 m (997 ft). From them, one may see a series of unique views of the Bay of Gibraltar, the isthmus, and Spain.

Second World War onwards

When World War II broke out in 1939, the authorities evacuated the civilian population to Morocco, the United Kingdom, Jamaica, and Madeira so that the military could fortify Gibraltar against a possible German attack. By 1942 there were over 30,000 British soldiers, sailors, and airmen on the Rock. They expanded the tunnel system and made the Rock a keystone in the defence of shipping routes to the Mediterranean.

In February 1997, it was revealed the British had a secret plan called Operation Tracer to conceal servicemen in tunnels beneath the Rock in case the Germans captured it. The team in the rock would have radio equipment with which to report enemy movements. A six-man team waited undercover at Gibraltar for two and a half years. The Germans never got close to capturing the rock and so the men were never sealed inside. The team was disbanded to resume civilian life when the war ended.

Sayings

1909 insurance advertisement Rock of Gibraltar - 1909 Prudential advert.jpg
1909 insurance advertisement

The saying "solid as the Rock of Gibraltar" is used to describe an entity that is very safe or firm. [9]

The motto of the Royal Gibraltar Regiment and Gibraltar itself is Nulli Expugnabilis Hosti (Latin for "No Enemy Shall Expel Us").

Nature reserve

Female Barbary macaque feeding her young at Mediterranean Steps, on the Rock of Gibraltar Female Macaque with young suckling.jpg
Female Barbary macaque feeding her young at Mediterranean Steps , on the Rock of Gibraltar

Approximately 40% of Gibraltar's land area was declared a nature reserve in 1993.

Flora and fauna

The flora and fauna of the Gibraltar Nature Reserve are of conservation interest and are protected by law. [10] Within it is a range of animals and plants, but the highlights are the Barbary macaques (the famous Rock apes), the Barbary partridges, and flowers such as Gibraltar's own chickweed, thyme and the Gibraltar candytuft.[ citation needed ] The Barbary macaques may have originated from an escape of North African animals transported to Spain; it is also possible that the original Gibraltar macaques are a remnant of populations that are known to have spread throughout Southern Europe during the Pliocene, up to 5.5 million years ago. [11] [12] Some animals of the Rock have been reintroduced by the Alameda Wildlife Conservation Park who have three Barbary macaques.

Birds

The Rock of Gibraltar, at the head of the Strait, is a prominent headland, which accumulates migrating birds during the passage periods. The vegetation on the Rock, unique in southern Iberia, provides a temporary home for many species of migratory birds that stop to rest and feed before continuing migration for their crossing over the sea and desert. In spring, they return to replenish before continuing their journeys to Western Europe, journeys which may take them as far as Greenland or Russia. [13]

The Rock has been identified as an Important Bird Area by BirdLife International, because it is a migratory bottleneck, or choke point, for an estimated 250,000 raptors that cross the Strait annually, and because it supports breeding populations of Barbary partridges and lesser kestrels. [14]

See also

Related Research Articles

Strait of Gibraltar Strait between the Atlantic and the Mediterranean

The Strait of Gibraltar, also known as the Straits of Gibraltar, is a narrow strait that connects the Atlantic Ocean to the Mediterranean Sea and separates the Iberian Peninsula in Europe from Morocco in Africa.

Europa Point

Europa Point, is the southernmost point of Gibraltar. At the end of the Rock of Gibraltar, the area is flat and occupied by such features as a playing field and a few buildings. On a clear day, views of North Africa can be seen across the Strait of Gibraltar including Ceuta and the Rif Mountains of Morocco; as well as the Bay of Gibraltar and the Spanish towns along its shores. It is reached from the old town by Europa Road.

Gorhams Cave Cave and archaeological site in Gibraltar; one of the last known habitations of the Neanderthals in Europe

Gorham's Cave is a sea-level cave in the British overseas territory of Gibraltar. Though not a sea cave, it is often mistaken for one. Considered to be one of the last known habitations of the Neanderthals in Europe, the cave gives its name to the Gorham's Cave complex, which is a combination of four distinct caves of such importance that they are combined into a UNESCO World Heritage site, the only one in Gibraltar. The three other caves are Vanguard Cave, Hyaena Cave, and Bennett's Cave.

Barbary macaques in Gibraltar

Originally from the Atlas Mountains and the Rif Mountains of Morocco, the Barbary macaque population in Gibraltar is the only wild monkey population on the European continent. Although most Barbary monkey populations in Africa are experiencing decline due to hunting and deforestation, the Gibraltar population is increasing. Currently, some 300 animals in five troops occupy the Upper Rock area of the Gibraltar Nature Reserve, though they make occasional forays into the town. As they are a tailless species, they are also known locally as Barbary apes or rock apes, despite being classified as monkeys. The local people simply refer to them as monos when conversing in Spanish or Llanito.

Geology of the Iberian Peninsula The origins, structure use and study of the rock formations of Spain, Portugal, Andorra and Gibraltar

The geology of the Iberian Peninsula consists of the study of the rock formations on the Iberian Peninsula, which includes Spain, Portugal, Andorra, and Gibraltar. The peninsula contains rocks from every geological period from the Ediacaran to the Quaternary, and many types of rock are represented. World-class mineral deposits are also found there.

El Estrecho Natural Park

El Estrecho Natural Park is a natural park in Spain, located on the northern side of the Strait of Gibraltar.

St. Michaels Cave Caves in Gibraltar

St. Michael's Cave or Old St. Michael's Cave is the name given to a network of limestone caves located within the Upper Rock Nature Reserve in the British Overseas Territory of Gibraltar, at a height of over 300 metres (980 ft) above sea level. According to Alonso Hernández del Portillo, the first historian of Gibraltar, its name is derived from a similar grotto in Monte Gargano near the Sanctuary of Monte Sant'Angelo in Apulia, Italy, where the archangel Michael is said to have appeared.

History of Gibraltar History of a peninsula on the Iberian coast

The history of Gibraltar, a small peninsula on the southern Iberian coast near the entrance of the Mediterranean Sea, spans over 2,900 years. The peninsula has evolved from a place of reverence in ancient times into "one of the most densely fortified and fought-over places in Europe", as one historian has put it. Gibraltar's location has given it an outsized significance in the history of Europe and its fortified town, established in the Middle Ages, has hosted garrisons that sustained numerous sieges and battles over the centuries.

Gibraltar Nature Reserve

The Gibraltar Nature Reserve is a protected nature reserve in the British Overseas Territory of Gibraltar that covers over 40% of the country's land area. It was established as the Upper Rock Nature Reserve in 1993 under the International Union for Conservation of Nature's category Ia and was last extended in 2013. It is known for its semi-wild population of Barbary macaques, and is an important resting point for migrating birds.

Moorish Gibraltar

The history of Moorish Gibraltar began with the landing of the Muslims in Hispania and the fall of the Visigothic Kingdom of Toledo in 711 and ended with the fall of Gibraltar to Christian hands 751 years later, in 1462, with an interregnum during the early 14th century.

North Bastion, Gibraltar

The North Bastion, formerly the Baluarte San Pablo was part of the fortifications of Gibraltar, in the north of the peninsula, protecting the town against attack from the mainland of Spain. The bastion was based on the older Giralda tower, built in 1309. The bastion, with a mole that extended into the Bay of Gibraltar to the west and a curtain wall stretching to the Rock of Gibraltar on its east, was a key element in the defenses of the peninsula. After the British took Gibraltar in 1704 they further strengthened these fortifications, flooding the land in front and turning the curtain wall into the Grand Battery.

Bray's Cave is a limestone cave in the British Overseas Territory of Gibraltar. Human remains and notable Neolithic and Bronze Age finds have been unearthed in the cave. Three almost complete skulls were recovered but the important find was that people had returned to the site to re-use it for funerals, other cranial fragments from other individuals were recovered, and it appeared that previous remains had been move aside for a more recent death.

Neanderthals in Gibraltar Neanderthals among the first Neanderthals to be discovered by modern scientists

The Neanderthals in Gibraltar were among the first to be discovered by modern scientists and have been among the most well studied of their species according to a number of extinction studies which emphasize regional differences, usually claiming the Iberian Peninsula partially acted as a “refuge” for the shrinking Neanderthal populations and the Gibraltar population of Neanderthals as having been one of many dwindling populations of archaic human populations, existing just until around 42,000 years ago. Many other Neanderthal populations went extinct around the same time.

Fortifications of Gibraltar

The fortifications of Gibraltar have made the Rock of Gibraltar and its environs "probably the most fought over and most densely fortified place in Europe, and probably, therefore, in the world", as Field Marshal Sir John Chapple has put it. 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 34 miles (55 km) of galleries had been dug in an area of only 2.6 square miles (6.7 km2).

Tunnels of Gibraltar

The tunnels of Gibraltar were constructed over the course of nearly 200 years, principally by the British Army. Within a land area of only 2.6 square miles (6.7 km2), Gibraltar has around 34 miles (55 km) of tunnels, nearly twice the length of its entire road network. The first tunnels, excavated in the late 18th century, served as communication passages between artillery positions and housed guns within embrasures cut into the North Face of the Rock. More tunnels were constructed in the 19th century to allow easier access to remote areas of Gibraltar and accommodate stores and reservoirs to deliver the water supply of Gibraltar.

Mediterranean Steps

Mediterranean Steps is a path and nature trail in the British Overseas Territory of Gibraltar. One of the footpaths of Gibraltar, the path is located entirely within the Upper Rock Nature Reserve and was built by the British military but is now used by civilians as a pedestrian route linking Martin's Path to Lord Airey's Battery near the summit of Rock of Gibraltar. The path offers views over the Strait of Gibraltar, Windmill Hill, Europa Point, the Great Sand Dune, Gibraltar's east side beaches, the Mediterranean Sea and the Spanish Costa del Sol.

Windmill Hill (Gibraltar) A pair of plateaux

Windmill Hill or Windmill Hill Flats is one of a pair of plateaux, known collectively as the Southern Plateaux, at the southern end of the British Overseas Territory of Gibraltar. It is located just to the south of the Rock of Gibraltar, which descends steeply to the plateau. Windmill Hill slopes down gently to the south with a height varying from 120 metres (390 ft) at the north end to 90 metres (300 ft) at the south end. It covers an area of about 19 hectares, though about 6 hectares at the north end is built over. The plateau is ringed to the south and east with a line of cliffs which descend to the second of the Southern Plateaux, Europa Flats, which is itself ringed by sea cliffs. Both plateaux are the product of marine erosion during the Quaternary period and subsequent tectonic uplift. Windmill Hill was originally on the shoreline and its cliffs were cut by the action of waves, before the ground was uplifted and the shoreline moved further out to the edge of what is now Europa Flats.

Caves of Hercules Moroccan cultural heritage site

The Caves of Hercules is an archaeological cave complex located in Cape Spartel, Morocco. Situated 14 kilometres (9 mi) west of Tangier, the popular tourist attraction is adjacent to the summer palace of the King of Morocco.

The footpaths of Gibraltar provide access to key areas of the Upper Rock Nature Reserve, a refuge for hundreds of species of flora and fauna which in some cases are found nowhere else in Europe. The reserve occupies the upper part of the Rock of Gibraltar, a long and narrow mountain that rises to a maximum height of 424 metres (1,391 ft) above sea level, and constitutes around 40 per cent of Gibraltar's total land area. The unusual geology of the Rock of Gibraltar – a limestone peak adjoining a sandstone hinterland – provides a habitat for plants and animals, such as the Gibraltar candytuft and Barbary partridge, which are found nowhere else in mainland Europe. For many years, the Upper Rock was reserved exclusively for military use; it was fenced off for military purposes, but was decommissioned and converted into a nature reserve in 1993.

University of Gibraltar Public University in Gibraltar

The University of Gibraltar is a degree-awarding higher education institution established by the Government of Gibraltar through the University of Gibraltar Act 2015. The founding of the university was described by Gibraltar's Chief Minister Fabian Picardo as "a coming-of-age" for the British Overseas Territory.

References

  1. "Rock of Gibraltar, Gibraltar". Peakbagger.com. Retrieved 2 August 2014.
  2. Google (5 March 2018). "Peak: Highest Point" (Map). Google Maps . Google. Retrieved 5 March 2018.
  3. 1 2 Welcome To The Rock of Gibraltar! by costarsure.com
  4. 1 2 "Pillars of Hercules". The Gibraltar Museum. Archived from the original on 20 July 2007. Retrieved 14 January 2008.
  5. Rodríguez Vidal, J.; et al. "Neotectonics and shoreline history of the Rock of Gibraltar, southern Iberia". researchgate.net. Elsevier (2004). Retrieved 23 June 2016.
  6. 1 2 3 4 5 Rose, E. P. F. & M. S. Rosenbaum (1991). A Field Guide to the Geology of Gibraltar. Gibraltar: The Gilbraltar Museum. p. 192.
  7. "1El relieve kárstico de Gibraltar como registro morfosedimentario durante el Cuaternario (Mediterráneo occidental)" (PDF). Boletín de la Sociedad Española de Espeleología y Ciencias del Karst (in Spanish): 7. 2002.
  8. Samuels, Kevin (20 April 2004). "Physical Geology 2004: The Rock of Gibraltar and Surroundings". Earlham College . Retrieved 5 July 2017.
  9. "the Rock of Gibraltar". Oxford Advanced Learner's Dictionary. Oxford University Press. Retrieved 28 October 2012.
  10. Charles Perez & Keith Bensusan (2005). "A Guide to The Upper Rock Nature Reserve" (PDF). The Gibraltar Ornithologicaland Natural History Society. Retrieved 28 October 2012.
  11. "DNA solves mystery of Gibraltar's macaques". Gibraltar News Online. 26 April 2005. Archived from the original on 27 September 2007. Retrieved 11 November 2009.
  12. C. Michael Hogan (19 December 2008). "Barbary Macaque: Macaca sylvanus". Globaltwitcher. Archived from the original on 19 April 2012. Retrieved 28 October 2012.
  13. "What to see". www.gibraltar.gov.uk. Archived from the original on 4 November 2011. Retrieved 28 October 2012.
  14. "Important Bird Areas factsheet: Rock of Gibraltar". BirdLife International. 2012. Retrieved 28 October 2012.