Take a refreshing dip
There are around twenty different beaches to choose from along the shores of Lake Mälaren and the banks of Eskilstunaån (the Eskilstuna river). In addition, Sundbyholm is the site of the longest sandy beach by Lake Mälaren, with plenty of room to sunbathe and to build sandcastles.
Vilsta, Mälarbaden and Borsökna are other great places to swim, and there are options that suit all tastes and preferences.