Gibraltar Arc Gibraltar Arc The Gibraltar Arc is a geological region corresponding to an arcuate orogen surrounding the Alboran Sea, between the Iberian Peninsula and Africa. It consists of the Betic Cordillera (south Spain), and the Rif (North Morocco). The Gibraltar Arc is located at the western end of the Mediterranean Alpine belt and formed during the Neogene due to convergence of the Eurasian and African plates. Maximum altitudes of the region are reached at the Mulhacén peak (3482 m) at the Cordillera Betica. Precipitation is collected mainly by the Guadalquivir (Betics) and Sebou (Rif) rivers, which have delivered most sedimentary infill
Lines of Contravallation of Gibraltar ruins of the fortifications, of which only a few fragmentary remains can be seen today. Following the Anglo-Dutch capture of Gibraltar in 1704 and the subsequent Twelfth Siege of Gibraltar, in which the Spanish and their French allies sought unsuccessfully to recover the territory, the Spanish built a permanent line of fortifications facing south across the isthmus. Construction began in November 1730 under the Marquis of Verboom with the intention that the lines would block any British invasion of Spanish territory mounted from Gibraltar, act as a starting point for any future Spanish operations against Gibraltar, and cut off access