Any campground suggestions near Fargo ND (can be in MN) and Sioux Falls SD?

[Boudicca908]

In September, my friend and I are going to be camping in Theodore Roosevelt NP (the North Unit) and Badlands NP & Rapid City SD environs.  After that, we are heading east and looking at spending a day near Fargo ND, and then a few days in the Sioux Falls SD area, to explore museums and local sights. West of Sioux Falls, we plan to go to the World's Only Corn Palace, in Mitchell SD. 

We prefer not to camp in the urban area. The closest federal camping I see is Cottonwood Recreation Area campground near Yankton SD (1.5 hours) and Left Tailrace near Thompson SD (2.5 hours). I've camped at Cottonwood and it was nice. But we would like to be closer to Sioux Falls. 

Any suggestions for the Fargo area and the Sioux Falls area would be appreciated. 

Edited 50 minutes ago by Boudicca908