In the Middle ages the navy and the merchant fleets of Venetia were the most powerful and numerous in the Mediterranean Sea. In the period of crusades (1096 - 1270) Venetia was the main supplier of naves, which were capable to take on board the ship up to 1500 people. In the course of the next century the construction of these ships constantly changed and by the beginning of the 16th century the Venetian four-masted nave had a sufficiently perfect form of her hull and significant dimensions: her maximal length was 28.7 m, the length in waterline was 25 m, her maximal breadth was 8.36 m, her draught reached to 3 m and her displacement was about 600 t. The fore- and the mainmasts carried square sails, the second main and the mizzenmast carried Latin sails. The total area of sails exceeded 770 square meters. Such a sail rigging made it possible to weather the ship, i.e. to go to windward of her. Large naves unlike other vessels had several anchors (up to 7) to prevent drifting during mooring.