| Lago di Bientina | |
|---|---|
 View of the former lakebed during a flood | |
  Lago di Bientina | |
| Location | Province of Lucca, Province of Pisa, Tuscany |
| Coordinates | 43°45′N 10°38′E / 43.75°N 10.64°E |
| Primary inflows | River Auser |
| Primary outflows | Canale Imperiale |
| Basin countries | Italy |
| Surface area | 36 km2 (14 sq mi) |
Lago di Bientina, also known as Lago di Sesto, was a lake in Tuscany, Italy. Located to the north of the town of Bientina, between Lucca and Pisa, the lake was historically subject to numerous efforts at drainage due to its tendency to flood. Early attempts at canal-building and drainage in the 16th century were hampered by the lake's connection with the Arno River, which often led to backflow and even increased flooding.
In the 19th century, by order of Grand Duke Leopold II, the lake was fully reclaimed and converted to farmland. Before drainage, it was the largest lake in Tuscany. The former lake-bed is drained by a series of canals, which flow through a channel called La Botte ('The Barrel') underneath the Arno River before emptying into the Canale Imperiale ('Imperial Canal'), and, subsequently, the Ligurian Sea.