Spinalonga in Crete
Spinalonga is a small island near Elounda in East Crete. Spinalonga is also known as the Leper Island, as that is where lepers from Crete and the rest of Greece were quarantined until 1957. Today thousands of tourists visit Spinalonga each summer by boat from Agios Nikolaos, Elounda and Plaka, for a tour of its ruined buildings, which the Archaeological Service is laboriously trying to maintain.
Today the name Spinalonga is only applied to the islet, but the Venetians used it to include the large peninsula of Nissi or Kolokytha, which is connected to Elounda by a narrow isthmus. Apparently Kolokytha used to be joined to Spinalonga (which is why it shared the same name), but in 1526 the Venetians cut a canal between the two, forming this small island.
This information comes from the Venetian cartographer Vincenzo Coronelli, but it may not be true. However, the islet is only 170 metres from Kolokytha and the water is shallow, so perhaps the Venetians did indeed carry out this project to form an impregnable island fortress.