Real Cittadella, Star fort in Messina, Italy.

Real Cittadella is a pentagonal star fort begun in 1680 by the Spanish Empire on the San Raineri peninsula, designed by military engineer Carlos de Grunenbergh. Five corner bastions—Norimberga, San Francesco, San Carlo, San Stefano and San Diego—were joined by curtain walls, with a cavalier on each and outworks including a ravelin and lunettes. Only the San Stefano and San Diego bastions and adjoining curtain walls survive above ground.

Built between 1680 and 1686 under Spanish rule, the fort required demolishing an existing neighborhood to make space for its construction. During the 1848 Sicilian uprisings, the structure resisted attacks until military reinforcements reached the city.

The pentagonal plan with five corner bastions, each topped by a cavalier, follows the 17th-century "fortification à la moderne" style. The monumental Porta Grazia, carved with rich stone ornament by Domenico Biondo, was dismantled in 1961 and rebuilt in Piazza Casa Pia dei Poveri, away from the fort.

Visitors can walk around the two surviving bastions and view the relocated gate at a nearby plaza. The remains are accessible from the outside, though interpretive materials on site are limited.

The fort was never taken by assault; it surrendered only after long sieges left it without supplies. In 1860 about 4,000 Bourbon soldiers under General Gennaro Fergola held it as the kingdom's last stronghold in Sicily, capitulating to Piedmontese troops on 12 March 1861.