Strängnäs Municipality is a municipality in Södermanland County in eastern Sweden, located by Lake Mälaren. Its seat is located in the city of Strängnäs.
The present municipality was created in 1971, when the City of Strängnäs was amalgamated with the City of Mariefred and a number of rural municipalities. Originally there were 15 local government entities in the area.
Wikipedia https://en.wikipedia.org/wiki/Strängnäs_Municipality
Coordinates 59°21'22.641" N 17°4'9.04" E
