The Strait of Gibraltar is a natural bottleneck at the junction of Mediterranean, North Atlantic, and West African shipping routes. The growth of the Europe / Asia trade has led to the increasing use of the strait for transshipment. Most of this transshipment takes the form of a dual competition between the established hub of Algeciras (on the Spanish side of the strait) and the new hub of Tanger Med (on the Moroccan side). When it opened in the late 2000s, Tanger Med saw the relocation of some of the transshipment activities taking place in Algeciras. Still, both hubs resumed their growth afterward, an ongoing trend as economies of scale continue to be applied to the major Asia / Middle East / Europe routes. They are pure transshipment hubs since more than 90% of their volume concerns transshipment cargoes that do not leave the port.
Valencia has also been an active transshipment hub despite involving a higher level of deviation from the main shipping lanes since it provides hinterland cargoes as well. The port of Sines in Portugal is also vying for a share of the transshipment business and recently overtook Las Palmas which has been a transshipment hub focusing on the West African trade, a role that has been eroded by the emergence of Tanger Med. A divergence is emerging between the mega-hubs of Algeciras, Tanger Med, and Valencia and the remaining ports of the region.