This post is also available in: Deutsch (German)
The Soltborgerkolk is an 11-minute drive from here. In the summer months you can swim here. And only costs a parking fee (approx. EUR 1). They also have a small kiosk that sells ice cream and chips.
Click on the link for the route: https://goo.gl/maps/KgcDBnBnx75nyGJy9