alfonsino castle and the sea fortress
The Alfonsino Castle (also called the 'Castle of the Sea' or the 'Red Castle' because of the colour of the carp stones used for its construction) is a fortified structure built on the island of Sant'Andrea, at the mouth of the outer harbour of Brindisi. The castle is adjacent to the Forte a Mare, whose construction began in 1558 during the reign of Philip II of Habsburg, son of Charles V. It lasted 46 years.
located on southern promontory

The castle and fortress from above
The Alfonsino Castle is located on the southern promontory and has irregular shapes that follow the structure of the site (it has also suffered collapses and alterations). Inside there is a hall with a washbasin with stone posts (16th century). The two bastions date from the end of the 15th century; the one facing inwards is round, the one facing the open sea is triangular.

The castle is lovely to visit around sunset, this is the inner harbour
Inner harbour
Characteristic is the small inner harbour, which is accessible via an open archivolt in the city walls, which connected the Aragonese construction with the Spanish expansion around 1577. On one side the fortification structure from the fifteenth century with a portal, on the other side the so-called 'opera a corno', which was built entirely in the style of the fortification architecture from the sixteenth century. This part is also preceded by a portal decorated with coats of arms.
The island is connected to the west coast by a dam that closes the inlet of Brindisi, also called Bocca di Puglia. Between the island and the south coast run two lines that narrow the harbour mouth to just 250 metres.
inhabited since 11th century
The island was inhabited at least since the 11th century by the ancient Benedictine abbey of Sant'Andrea all'Isola (few remains of it remain, notably the capitals, which can be seen in the Provincial Archaeological Museum Francesco Ribezzo in Brindisi). However, it was abandoned after a series of dramatic events that shook the city (14th-15th centuries).
the first tower
In 1445, Alfonso V of Aragon decided to build a first tower. This served as a defence post for the harbour at the end of the island. In 1481, the work was extended to the north-east. From 1558 to 1604, much of the rest of the island was surrounded by bastions (forts and lakes). The last part was separated by a cut in the rock that served as a moat. This created a complex system of fortifications to defend the harbour.
The area is associated with several war events, including the attack on sixteen Venetian galleys (1528) that were surprised by the newly built artillery, and the French siege of the counter-revolutionary Boccheciampe (1799). The island served as a military hospital for a long time, after which it fell into the hands of the navy.
Restorations
A storm surge caused severe damage to the wall structure and led to the island being dismantled in 1984. The long and important restoration phase of the entire complex is almost complete. The building is still regularly opened to visitors and cultural events are held there.

A coat of arms on the castle
VISITING THE CASTLE
The Castle, due to the uniqueness of the site, is accessible exclusively through guided tours conducted by specialized personnel. The reservation can be made on the portal pastpuglia.it or by downloading the application PastPuglia,