The conformation of the Bay of Cartagena de Indias, oriented longitudinally from north to south with two access mouths: Bocagrande and Bocachica, determined the special location of the military fortifications.
According to Rodolfo Segovia Salas, scholar and author of several works on the fortresses of Cartagena de Indias and the Greater Caribbean, the Bay of Cartagena is divided into two large natural basins with very different defense problems: the Outer Bay bounded by the Bocagrande peninsula, the continent, and the islands of Tierrabomba, Barú and Manzanillo; and the Inner Bay that housed the colonial port, also surrounded by Bocagrande and the continent, and by the islands of Manzanillo and Manga.
