Construction of the Castello Aragonese in the suburb of Baia in Bacoli had been deemed necessary in order to be able to withstand pirate attacks. In the course of the centuries, it was transformed multiple times, in order to be able to accommodate new functions. It is presently the seat of the Museo Archeologico dei Campi Flegrei.
Castello Aragonese Bacoli
Useful information
Address: . Phone: . Opening times: Tuesdays to Sundays from 09:00 till 14:20. Closed: Mondays. Ticket price: 4 Euros (ages 18 to 25 2 Euros and ages 65+ and 18- free). (Note that opening times and admission may be subject to change.)

History and description
The Castello Aragonese of Bacoli was built on top of the ruins of a Roman villa, after the city had been attacked by the “Moors”. The name “Moors” did not really indicate one specific people at the time, but could refer equally to northern African Muslims, Sicilians, Maltese or Spanish pirates.
Construction started in 1495.
Between 1538 and 1550, the castle was completely reconstructed by the Spanish viceroy Pedro da Toledo.
In 1887, after the Unification of Italy, it stopped being used as a fortress.
During World War I it was a prison and in 1926 it became an orphanage.
Since 1993, it is the seat of the Archaeological Museum of the Phlegreian Fields.