Originally San Felice was just a small island protruding from the water to the north of the ancient Clodia Minor, containing a wooden tower which marked the entrance to the lagoon. After the War of Chioggia it was recongnised as a site of prime strategic signifiance for ensuring the security of the Southern Lagoon. This led to the building of the Castello della Luppa (or Lova) between the 15th and 16th centuries. Thanks to the subsequent rebuildings, which began immediately after the end of the War of Chioggia (1384) and continued till the fall of the Venetian Republic (1797), we arrived at the present structure of the island. Seen from above, it resembles a five-pointed star, on the model of the castle of Famagusta in Cyprus and other Venetian fortifications. This structure allows 360° surveillance both over the lagoon and over the sea, and has proved itself a powerful obstacle to the high tides which continued to erode the island from the sea and from the lagoon. A still visible feature which is very interesting from the architectural point of view, is the gateway in Istrian stone, designed by A. Tirali at the beginning of the 18th century, with the rest of the fortifications. The island is also very interesting for its natural history. Currently, it is not possible to visit it. It awaits a reassessment of its use taking account of the environmental qualities, after the Navy occupation of the last two centuries. A walk or a cycle ride reveals landscapes and views which are absolutely unique, and a dramatic perspective on the city skyline, especially at sunset.