NASI, LAKE

Finnish Nsijrvi, lake in Hme lni (province), southwestern Finland. It extends northward from the city of Tampere, northwest of Helsinki. Approximately 20 miles (32 km) long and 2 to 8 miles (3.2 to 13 km) wide, it is the largest of the Pyh lakes and the central lake of the western branch of the system. Lake Vanka, the northern arm of Lake Nsi, is connected by canal (built 1854) to Lakes Palo and Ruo. This route allows passenger ferry service to connect the town of Ruovesi with Tampere to the south. Ferry service has operated on Lake Nsi since 1858. Lake Nsi drains southward into the Pyh lakes via the Tammer Rapids. The southern banks of the lake are flat and barren, whereas the northern shore is more developed. The village of Teisko is located on the eastern shore.