Kangasniemi is a municipality in the Southern Savonia region, Finland. The municipality has a population of 5,095 (31 August 2024) and covers an area of 1,326.75 square kilometres (512.26 sq mi) of which 256.86 km2 (99.17 sq mi) is water. The population density is 4.77 inhabitants per square kilometre (12.4/sq mi).
Kangasniemi is located on the Finnish national road 13, 50 km (31 mi) northwest of Mikkeli and 63 km (39 mi) southeast of Jyväskylä. Distance to the national capital, Helsinki is 250 km (160 mi). Its neighbour municipalities are Hankasalmi, Hirvensalmi, Joutsa, Mikkeli, Pieksämäki and Toivakka.
There are almost 3600 (May 2014) summer houses, and summer guests redouble the number of inhabitants during the summer months.
The municipality is unilingually Finnish.
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