The Venetian Arsenal (Italian: Arsenale di Venezia) is a complex of former shipyards and armories clustered together in the Republic of Venice in northern Italy. Owned by the state, the Arsenal was responsible for the bulk of Venice's naval power during the middle part of the second millennium AD. It was "one of the earliest large-scale industrial enterprises in history".
Construction of the Arsenal began around 1104, during Venice's republican era. It became the largest industrial complex in Europe prior to the Industrial Revolution, spanning an area of about 45 ha (110 Acres), or about fifteen percent of Venice. Surrounded by a 2 mi (3.2 km) rampart, laborers and shipbuilders regularly worked within the Arsenal, building ships that sailed from the city's port. With high walls shielding the Arsenal from public view and guards protecting its perimeter, different areas of the Arsenal each produced a particular prefabricated ship part or other maritime implement, such as munitions, rope, and rigging. These parts could then be assembled into a ship in as little as one day. An exclusive forest owned by the Arsenal navy, in the Montello hills area of Veneto, provided the Arsenal's wood supply.
The Arsenal produced the majority of Venice's maritime trading vessels, which generated much of the city's economic wealth and power, lasting until the fall of the republic to Napoleon's conquest of the area in 1797. It is located in the Castello district of Venice, and it is now owned by the state.