The Fort St. John Baptist Berlengas, aka Berlengas Fortaleza, located on the island of Great Berlenga in the archipelago Berlengas, integrating all defensive Peniche.
The fort has a plant in the shape of an irregular polygon heptagonal. On the embankment, the side facing the island, presents the main building with two floors, with twelve compartments where they operated the service areas (House of the Command, Headquarters Troop, Stores, Kitchen and others) and eight magazines registered within walls. An unlit hall way gives access to various points inside the structure. Facing the sea ripping eleven gunboats.
The fort was built in the context of the War of Restoration, under the rule of King John IV (1640-1656). Although no one knows the exact date on which the works were initiated as early as 1655, when he was still under construction, successfully resisted their first assault, while being bombarded by three Turkish flag vessels.
During the Peninsular War was used as a support base for British forces in a guerrilla campaign in which the population of actively cooperating Peniche.
Later underwent renovation work, with the rebuilding of the chapel inside.
During the Portuguese Civil War (1828-1834), the fortress was in the hands of supporters of Miguel of Portugal (1828-1834).Deficient in artillery, however, resisted the assault on the liberals who used it as a basis for the assault on the citadel of Peniche, Miguel's stronghold.
Without greater military value, given the evolution of means of warfare in the nineteenth century, was dismantled (1847) and abandoned and was used as a support base for commercial fishing.