Fort Ridgely State Park

This is a nice state park campground, 31 sites, 15 of which are electric. Sites 23e, 25e, 29e, and 31e all have electric and are right along the creek (which you can hear when you wake up, it's super pleasant). I'd avoid 29e though, as it's right next to the bridge that leads to the trails, so there's lots of foot traffic. 18 is the only pull-through site, but there's no electric service there.

I stayed at 31e, which is especially great if you're setting up a tent: it's got a section off to the side, surrounded by trees on two sides and the creek on another.

In July 2016, there was no Verizon, T-Mobile, or Sprint coverage, but there was AT&T coverage. If you drive to the historic site in the state park (a few minutes by car) there's good service Verizon and T-Mobile.

Campground map: http://files.dnr.state.mn.us/maps/stateparks/spk00151camp.pdf