Forte Treporti is near Lio Grando and is locally better known as Forte Vecchio. Built on the ruins of an earlier French fort, it was built by the Austrians in the latter half of the 19th century (1845-51) in order to defend the lagoon and the Punta Sabbioni harbour entrance. At a due distance from Venice it was equipped with appropriate anti ship armaments on its sea facing side and defensive artillery on the Venetian lagoon side too. The main, west facing façade overlooking the lagoon has two entrances: one overlooking a service field and another larger and more important one with a portal and originally a drawbridge which accessed an inner courtyard. Two telemetry towers were built there during the Great War, one with a round base and one with a square base designed to observe enemies and calculate firing trajectories. Today part of Forte Treporti is lived in and its rooms are also used by a number of sporting and cultural associations.
Text from the book "Le Fortificazioni - Frammenti di guerra"
More here: www.viadeiforti.it