Human occupation on Berlenga Grande dates back to antiquity: the islands are referred to in Ptolemy's Geography as Λονδοβρίς (Londobris). Much later it was referred to as the island of Saturno by Roman geographers, and was visited successively by Muslims, Vikings and pirates/privateers from England and France.
In 1513, with the support of Queen Eleanor of Viseu, monks from the Order of São Jerónimo established a settlement on the island to offer assistance to navigation and victims of frequent shipwrecks. The monastery founded there (the Monastery of the Misericórdia da Berlenga), remained until the 16th century, when disease, lack of communication (due to constant inclement weather) and regular assaults by pirates and privateers (from England and France), forced the monks to abandon their service on the island.
After the Portuguese Restoration War, during the reign of King John IV, the Council of War determined that the demolition of the monastery ruins, and the use of their rocks to build a coastal defense would help protect the coastal settlements; the Fort of São João Baptista das Berlengas was constructed from the remnants of the monastery ruins. By 1655, it had already, during its construction, resisted an assault by three Barbary coast pirates.[clarification needed]
The island's lighthouse (dubbed Duke of Braganza by locals) was constructed in 1841. In the 20th century a solar panel was installed in the lighthouse's 29 metres (95 ft) column, providing a 50 kilometres (31 mi) field of vision.
The International Coordinating Council of UNESCO’s Man and the Biosphere Programme (MAB), meeting in Dresden (Germany) from 28 June to 1 July, while adding 18 new sites, included the Berlengas to the World Network of Biosphere Reserves (WNBR): in a statement on 30 June 2011, the list of classified reserves were presented.
The archipelago is made up of the largest island, Berlenga Grande, and two groups of smaller islets, the Estelas Inlets and the Farilhões-Forcados Islets. As the archipelago has been declared a reservation area for the protection of the local fauna (primarily sea birds), it is only visited by scientists and, in the summer, by a small number of tourists.