The Strait of Gibraltar crossing is a hypothetical

bridge A bridge is a structure built to span a physical obstacle (such as a body of water, valley, road, or rail) without blocking the way underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually someth ...

or tunnel spanning the Strait of Gibraltar (about 14 km or 9 miles at its narrowest point) that would connect

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

and

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

. The governments of

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = '' Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , ...

and

Morocco Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to A ...

appointed a joint committee to investigate the feasibility of linking the two continents in 1979, which resulted in the much broader Euromed Transport project. In January 2021, it was reported that the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and ...

and

would discuss building the crossing between

Gibraltar ) , anthem = " God Save the King" , song = "Gibraltar Anthem" , image_map = Gibraltar location in Europe.svg , map_alt = Location of Gibraltar in Europe , map_caption = United Kingdom shown in pale green , mapsize = , image_map2 = Gibr ...

and Tangiers.

Bridge

Several engineers have designed bridges on various alignments and with differing structural configurations. A proposal by Professor T.Y. Lin for a crossing between Point Oliveros and

Point Cires , french: Point Cires, es, Punta Cires , sobriquet = , image_name = , image_size = , image_caption = , image_alt = , image_map = , locator_map = , locator_map_size = , map_caption = , ...

featured deep piers, a length of , towers, and a span, more than twice the length of the current longest bridge span. A 2004 proposal by architect

Eugene Tsui Eugene Tssui ( born Eugene Tsui, September 14, 1954) Eugene Tsui, ''Evolutionary Architecture: Nature as a Basis for Design'' ( John Wiley & Sons, 1999), . is an American architect noted for his use of ecological principles and "biologic" desi ...

was for a floating and submerged bridge connected at a three-mile wide island in the middle of the

Mediterranean Sea The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on ...

Tunnel

Various tunnels have been proposed. Spain first proposed a modern tunnel under the Strait of Gibraltar in 1930. A major problem arose when the engineers hired by the Spanish government discovered that the material under the Strait was extremely hard rock, making tunnelling impossible with the available technology. One engineering solution was to fix, using cables, a prefabricated concrete tunnel to the floor of the Strait. This tunnel would handle automotive and train traffic. A 2008 geological study cast doubt on the tunnel's feasibility. In March 2009, a contract was issued for a joint system linking the Moroccan (SNED) with its Spanish counterpart, (SECEGSA). A three-year study for a

railway Rail transport (also known as train transport) is a means of transport that transfers passengers and goods on wheeled vehicles running on rails, which are incorporated in tracks. In contrast to road transport, where the vehicles run on a p ...

tunnel was announced in 2003. SNED and SECEGSA commissioned several seabed surveys. The Strait depth extends to on the shortest route, although it is only about 300 metres deep slightly further west, in a region known as the

Camarinal Sill The Camarinal Sill is the sill separating the Mediterranean Sea and the Atlantic Ocean. This threshold is the shallowest seafloor pass between the Iberian Peninsula and Africa. It is located approximately 25 km west of the narrowest section of ...

; the European and African

tectonic plates Plate tectonics (from the la, label=Late Latin, tectonicus, from the grc, τεκτονικός, lit=pertaining to building) is the generally accepted scientific theory that considers the Earth's lithosphere to comprise a number of large ...

meet around this area. The shortest crossing is . The proposed route of is west of Tarifa and to the east of

Tangier Tangier ( ; ; ar, طنجة, Ṭanja) is a city in northwestern Morocco. It is on the Moroccan coast at the western entrance to the Strait of Gibraltar, where the Mediterranean Sea meets the Atlantic Ocean off Cape Spartel. The town is the capi ...

. The tunnel is likely to be about in all. It is proposed that a connection would have to be made to the Spanish high speed railway network, which has a line projected to be built from Cádiz to Málaga via Algeciras. A report on the feasibility of the tunnel was presented to the EU in 2009. A further project study is under development by a group of specialist consultants from SYSTRA, Amberg and COWI.

Planning

The political origins of the project arise from the Common Hispanic-Moroccan Declaration of Fez, of 16 June 1979, and signed by the kings of Spain and Morocco. One consequence of the declaration was the creation in of SECEGSA, the Spanish government-funded corporation whose job is to "study" and "promote" the crossing. In December 2003, Spain and Morocco agreed to explore the construction of an underwater rail tunnel to connect their rail systems. The tunnel would have linked

Cape Malabata __NOTOC__ Cape Malabata (french: Cap Malabata; es, Punta Malabata; ar, رأس ملباطا, ''Ras Malabata'', or ''Rās al-Manār'', "Lighthouse Cape") is a cape located about east of central Tangier, Morocco, facing the Strait of Gibraltar. T ...

near

with Punta Paloma in the El Estrecho Natural Park west of

. In late 2006, Lombardi Engineering Ltd, a

Swiss Swiss may refer to: * the adjectival form of Switzerland *Swiss people Places * Swiss, Missouri *Swiss, North Carolina * Swiss, West Virginia *Swiss, Wisconsin Other uses * Swiss-system tournament, in various games and sports * Swiss Internation ...

engineering and design company, was retained to draft a design for a railway tunnel. According to the company, the main differences between the construction of this tunnel and that of the

Channel Tunnel The Channel Tunnel (french: Tunnel sous la Manche), also known as the Chunnel, is a railway tunnel that connects Folkestone (Kent, England, UK) with Coquelles ( Hauts-de-France, France) beneath the English Channel at the Strait of Dover ...

, linking

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...

and

Great Britain Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It ...

, are the depth of the sea and the geological conditions. The area under the Strait is less stable than that under the English Channel. An active major geologic fault, the

Azores–Gibraltar Transform Fault The Azores–Gibraltar Transform Fault (AGFZ), also called a fault zone and a fracture zone, is a major seismic zone in the Eastern Atlantic Ocean between the Azores and the Strait of Gibraltar. It is the product of the complex interaction betwee ...

, bisects the Strait, and severe earthquakes have occurred in the area. The presence of two deep Quaternary clay channels in the middle of the Strait makes construction complex, causing doubts about the feasibility of the project and proposals for an exploratory tunnel. No official figures about the cost of the project had been announced by 2007, but previous estimates exceeded €5 billion.

Technical aspects

The proposed rail tunnel's length is , deep, and its construction would take 15 years. An earlier plan was to link the two continents via the narrowest part of the strait, but this idea was dismissed as the tunnel would be below sea level. For comparison, the currently deepest undersea tunnel, the Norwegian

Ryfylke Tunnel The Ryfylke Tunnel ( no, Ryfylketunnelen) is an undersea road tunnel in Rogaland county, Norway. It is part of the Norwegian National Road 13 running between Stavanger and Ryfylke (district) under the Horgefjord (part of the Boknafjord). Th ...

, is below sea level. A tunnel deeper than Ryfylke is under construction, also in Norway;

Rogfast Rogaland Fixed Link or simply the Rogfast is a project, constructing a sub-sea road tunnel between the municipalities of Randaberg (near the city of Stavanger) and Bokn in Rogaland county, Norway. The tunnel will be called the Boknafjord tunnel ...

will be long and deep, expected to be completed in 2028–29. The construction of terminals, such as the Eurotunnel Folkestone Terminal and

Eurotunnel Calais Terminal The Eurotunnel Calais Terminal (also known as the Charles Dickens Terminal or Coquelles Terminal) is a railway terminal built for the transport of road-going vehicles on specially constructed trains through the Channel Tunnel. The terminal is ...

at either end of the

, might be required for trans-shipment of road vehicles.

References

External links