Cartagena de Indias as a key city for the Spanish Empire since its beginning was a military objective to then rival countries such as England and France. For this the fortification of the city was indispensable to secure victory in case of an enemy assault.
The process of fortification of the entire city and its surroundings started in the Colony in the XVIth century and went on until the end of the XVIIIth century, a few years before the Independence epoch. The Fuerte del Boquerón was the first in Cartagena de Indias, and came up from the need to cover the entrance to the Bahía de las Animas and make any disembark or nearby massive penetration more difficult. This fort was located where today stands the Fuerte San Sebastián del Pastelillo, on the island of Manga. The Boquerón was aided by batteries that prevented free access to any of the invasion routes to the city.
There were two batteries near the bulwarks of Santa Catalina
and San Lucas, where today is El Cabrero, which protected the access by land on the northern side of the city. Two more batteries located at Punta Icacos (where today stands the Hotel Caribe) defended the entrance through the south. Two batteries where today stands the Bulwark Santo Domingo, protecting the frontal access from the sea and the Peninsula of Bocagrande.
Though these defenses were not enough to protect the city, which fell under the invasions of Martin Cote, and Francis Drake. This forced the Spanish Crown to design a serious fortification project, made by the italian engineer Bautista Antonelli, to convert Cartagena de Indias in the best fortified plaza in America.
In the XVIIth century the entrances to the bay through Tierrabomba were protected by the castle San Luis de Bocachica at the south and San Matías which replaced the batteries at Punta Icacos. This crossed fires with the Plataforma Santangel located on the northern side of Tierrabomba and disappeared due to its inefficiency
The Fuerte de Santa Cruz de Castillogrande was located at Punta del Judío (where actually stands the Club Naval) and crossed fires with Fuerte de Manzanillo, located on the island with the same name at the other side of the channel
The Bulwark Del Reducto was located on one of the ends of the then island of Getsemaní and crossed fires with El Boquerón, the same as the Puerta de la Media Luna, where the city communicated with mainland.
At the Cerro de San Lázaro was the fort with the same name, which years later would transform into the Castillo San Felipe with reforms and attachments that would make it more powerful.
In the XVIIIth century the military construction became important in Cartagena de Indias. The military engineer Don Juan
de Herrera y Sotomayor would be in charge of repairing the buildings destroyed in Vernon's invasion.
The Castle San Luis de Bocachica and the Castle San Felipe de Barajas were restored.
The batteries Chamba, San Felipe and Santiago,
located on the exterior coast of Tierrabomba were rehabilitated.
Two other batteries on the island of Barú, Varadero and Punta Abanico were also rehabilitated.
The forts of Manzanillo and Castillogrande were reconstructed.
Another engineer, Juan Bautista Mac Evan, would out stand for the conception of the project of the Castle San Fernando de Bocachica (realized by Lorenzo de Solis and Antonio de Arévalo) replacing San Luis which anyhow was useless.
The project of the fort of San Sebastián del Pastelillo was also planned. In the second half of the XVIIIth century, Don Antonio de Arévalo would be in charge of finishing the fortress of the plaza to make it completely impregnable.
Arévalo reinforced the Castle San Felipe with lateral batteries making it still stronger.
He built the Escollera de la Marina, that went from the Bulwark Santa Catalina to the bulwark Santo Domingo and protected the walls from the sea waves.
Concluded the Castle San Fernando in Bocachica and its respective batteries: Angel San Rafael (restored today), San Francisco
Regis and Santiago.
He also built the Espigón de Santa
Catalina (badly known today as La Tenaza), to repel the land raids that came from Marbella.
He built La Tenaza, located in front of the bulwarks of Santa Catalina and San Lucas; as well as the batteries of Más, Crespo
and the Hornabeque de Palo Alto, which don't exist today.
He made the Escollera de Bocagrande, an impressive submarine work destined to stop the passing of ships through the Boca Grande, between
Punta Icacos and Tierrabomba.
The last work of Arévalo was the construction of the bomb proofed vaults between the bulwark of Santa Catalina and the bulwark of Santa Clara. This work would conclude the systematic closure of the walled city.
This was also the last military building raised by Spain in Cartagena de Indias towards the end of the
XVIIIth century, when the XIXth century was coming with the Independence Revolution.