El fuerte de Santa Cruz y el conjunto defensivo español de Orán-Argelia

[EN] The fort of Santa Cruz in Oran (Algeria) represents the peak of the iceberg of a very huge and developed defence system. Its strategic situation has been the key of the failure and the success of this system. In 1708 the Turkish army took control of Oran by mining the escarpment of Santa Cruz. When Spanish returned in 1732 their first goal was to secure the city by securing the fort of Santa Cruz. In this way the Spanish kings sent many famous engineers of that moment to develop Santa Cruz project thinking in a very original solution which was sculpting a gorge in the mountain to isolate the fort of the tableland, blocking this way any attempt to mine the fort. Our communication will treat those projects to analyse how Santa Cruz passed from being the weakness of the defence system to be its strongest point.