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
South Bastion, Gibraltar South Bastion, Gibraltar The South Bastion was part of the fortifications of Gibraltar, protecting the western base of the Charles V Wall. It was originally built by Spanish military engineers, later improved by the British. The South Bastion stands at the south end of the Line Wall Curtain which defends the town from attack from the Bay of Gibraltar. Another curtain wall runs east from the bastion to the base of a precipice. This wall is pierced by the Southport Gates, guarded by the South Bastion and the Flat Bastion on either side. The Milanese military engineer Giovanni Battista Calvi