Where's the closest open H2O to MN?

[MINNOW]

I want to go fishing, but all the water in MN turned hard. Does anyone have any info on when the Iowa muskie waters freeze, or will I have to go further south? Does anyone know much about the Iowa waters? Like are they good in the fall etc. Never tried them and don't hear much about them either. Maybe its a conspiracy to keep the MN guys away?

Thanks,

Bryan