Spinalonga was fortified in the 16th century by the Venetians. It is one of the most well preserved examples of bastion fortresses in Crete. The ramparts were built in 1579. The islet remained in Venetian hands until 1715, when the fortress surrendered to the Ottomans.
Between the years 1903 – 1957 the islet functioned as a leper colony, one of the last ones in Europe.
Nowadays it attracts more than 300,000 visitors per year.