Spinalonga (Greek: Σπιναλόγκα) is an island in the Gulf of Elounda, north-eastern Crete, in the municipality of Agios Nikolaos, Lasithi, next to the town of Plaka in the area of Kalydon. It is near the Spinalonga peninsula (“large Spinalonga”) – which often causes confusion as the same name is used for both.
Following Venetian rule, when it was a fortress, the island became a leper colony.
Origin of the name
According to Venetian documents, the name of the island originated in the Greek expression στην Ελούντα stin Elounda (meaning “to Elounda“). The Venetians could not understand the expression, so they familiarized it using their own language, and called it spina “thorn” longa “long”, an expression that was also maintained by the locals.[1] The Venetians were inspired for this expression by the name of an island near Venice called by the same name and which is known today as the island of Giudecca.[citation needed]
History
Because of its position, the island was fortified from its earliest years in order to protect the entranceway of the port of Ancient Olous.[citation needed]
Arab raids
Olous, and accordingly the wider region, were depopulated at the middle of the 7th century because of the raids of the Arab pirates in the Mediterranean. Olous remained deserted until the mid-15th century, when the Venetians began to construct salt-pans in the shallow and salty waters of the gulf. Subsequently, the region acquired commercial value and became inhabited. This, in combination with the emergent Turkish threat, particularly after the Fall of Constantinople in 1453, and the continuous pirate raids, forced the Venetians to fortify the island.[citation needed]
Venetian rule
Further information: Venetian Crete

In 1578 the Venetians hired the engineer Genese Bressani to plan the island’s fortifications. He created blockhouses at the highest points of the northern and southern side of the island, as well as a fortification ring along the coast that countered any hostile disembarkation. In 1579, the Provveditore generale di Candia, Luca Michiel, laid the foundation stone of the fortifications, built over the ruins of an acropolis. There are two inscriptions that cite this event, one on the transom of the main gate of the castle and the other on the base of the rampart at the north side of the castle.
In 1584, the Venetians, realising that the coastal fortifications were easy to conquer by the enemies attacking from the nearby hills, decided to strengthen their defense by constructing new fortifications at the top of the hill. The new Venetian firepower had longer range, rendering Spinalonga an impregnable sea fortress, one of the most important in the Mediterranean basin.[citation needed]
Spinalonga, along with Gramvousa and Souda, remained in Venetian hands after the rest of Crete fell to the Ottomans in the Cretan War (1645–1669). In 1715, Spinalonga was taken over by the Ottomans during the last Ottoman–Venetian War.[2] These three forts defended Venetian trade routes and were also useful bases in the event of a new Venetian-Turkish war for Crete.[3] Many Christians found refuge in these fortresses to escape persecution from the Ottoman Turks.[citation needed]