Lake Iseo is a lake basin in Northern Italy, located in Lombardy.

Its main tributary and outlet is the Oglio river. It has an area of ​​65,3 km² and a maximum depth of 251 meters (5 ° for depth in Italy). It is located at 180 m of altitude in the Pre-Alps, at the bottom of the Val Camonica; it is wedged between the provinces of Bergamo and Brescia and hosts the largest natural lake island in Italy as well as the highest lake island in Europe: Monte Isola, to which the two islets of Loreto and San Paul. It also contains more than 500 different animal species including mouse fish.