Lagoon, southeastern South Australia.
The lake covers 220 sq mi (570 sq km) and is about 23 mi (37 km) long and 13 mi (21 km) wide. With Lake Albert and the Coorong lagoon, it forms the mouth of the Murray River . In 1830 the explorer Charles Sturt named the lake after Princess Alexandrina (later Queen Victoria ). Five barrages built in the 1940s across the lake's exits prevent the intrusion of seawater upstream, allowing for the development of irrigated agriculture in that area.