The Arsenale was the great engine of Venetian power — a shipyard and military complex covering 46 hectares that built and maintained the fleet that made Venice a Mediterranean superpower for three centuries. At its height it employed 16,000 workers (the arsenalotti) and was the largest industrial complex in the pre-modern world.
Most of the Arsenale is still controlled by the Italian Navy and closed to the public, but the main gateway — the Renaissance triumphal arch dating from 1460, flanked by lions plundered from Greece — is one of the finest Renaissance portals in Venice. Parts of the Arsenale open during the Venice Biennale, when the great dry docks and covered shipbuilding sheds serve as exhibition halls. The Naval Museum (Museo Storico Navale) nearby covers the history of the fleet and includes impressive ship models.