Wikipedia
Näsijärvi is a lake above sea level, in Pirkanmaa region, Finland. Näsijärvi is the biggest lake in the Tampere region at in size. The city of Tampere was built around the rapids of Tammerkoski, through which the lake drains into Pyhäjärvi. The water quality of the lake has improved as forest industry has decreased the amount of waste water.
There are boat cruising services on Näsijärvi. The steamer SS Kuru suffered the most severe Finnish inland shipping disaster on Näsijärvi.
During the winter, usually during February and March, the lake is frozen in its entirety. Näsijärvi is then used for Nordic walking, cross-country skiing, and everyday pleasure walking. There is a small, rocky island upon which a lighthouse resides, called Siilinkari – it is the most popular walking destination on the lake.
In the north Näsijärvi has a wide catchment area that includes among others the lakes Ruovesi, Kuorevesi, Keurusselkä, Tarjanne, Pihlajavesi, Toisvesi and Ähtärinjärvi.