Judge Magney State Park

This is a rustic state park with no electric sites, dump station or water source for RV tanks, as well as nearly non-existent cell service, but it's a pleasant getaway spot. It felt like a rustic forest campground but had amenities like a bathroom/shower house. Regarding water, there is drinking water available to fill containers, just no hookup to fill RV tanks. They also have trash and recycling dumpsters available.

The sites are decent size; privacy depends on the site but most aren't crammed on top of each other. All sites are dirt/gravel and the roads are dirt so be prepared for some dust in dry conditions.

We saw mostly tents and smaller rigs but that's probably due to no electricity and no water source for RVs to fill from. Still, some sites were large enough for the Class As that were there.

Bathrooms were decent but be ready for push-button showers for water conservation. Another reviewer said they last 7 seconds but it's longer than that now. They run long enough to essentially do Navy showers, which works fine. Water never really hot but plenty warm enough to not be considered cold.

Each site has a picnic table and fire ring, plus firewood is available at the front office or at the camp host site (via self-service). Front office rarely staffed but there is a work garage and the DNR staff came through the campground regularly.
Little to no cell service on T-Mobile and Verizon, but there is a WiFi spot available near the DNR work garage.

It's nice that you can hike from the campground to Devil's Kettle and another waterfall (same trail), both of which were great.

Access is from Highway 61 down a relatively short dirt road We would stay here again.

There was no hookup, not even electric, and no cell service, but that didn’t matter to me. There was a bathhouse, recycling, lots of shade, firewood, friendly park rangers, and an awesome hike to Devil’s Kettle Falls. My only complaint... the push button lukewarm showers run for literally 7 seconds. They take water conservation very seriously.
We were going to use this as a base to visit Isle Royale, but I made the fatal mistake of NOT reserving the ferry months in advance. (Frowny Face) Oh well...we saw Grand Portage NM and Split Rock Lighthouse SP instead. North Shore is just beautiful.

This is a no-frills campground right off Highway 61. There are no power hookups, though there is trash and recycling service, a shower building, and drinking water available. Privacy is hit or miss. The entire campground is covered on Google Street View, so you can virtually walk around the campground and pick a site, if that helps. Being so close to the highway, there is noise. This could be obnoxious in a tent, but probably is of little concern in an RV. Trucks passing by are extremely loud. I don't suggest staying here if you are sensitive to noise.

This park has excellent hiking, and it's also a great "home base" to explore the Arrowhead region, including the Superior National Forest, north to Grand Portage or south to Grand Marais, the Gunflint Trail, etc. I've also kept my trailer here and gone up to Thunder Bay or Sleeping Giant for a day-trip, not having to worry about which foods I can bring across the border.

Cell service in campground as of June 2019, without a booster:

Verizon: Unreliable, fluctuated between 1 bar LTE, to 1 bar 1x, to no service. Phone calls don't work. When I did have LTE, it speed tested at 187ms ping, 0.14mbps down, 0.09mbps up. You won't want to actively use it, but you should be able to get notifications, though possibly with a few minute delay during fluctuations.

AT&T: AT&T maintained 1 bar LTE with more stability than Verizon, but I struggled to get a data connection. Websites would not load at all. Attempted doing a speed test and it was preliminarily 0.03mbps with 805ms pings.

T-Mobile: Reliable and usable LTE connection, 53ms ping, 14.8mbps down, 1.1mbps up.

The above is without a booster of any kind. When I was here in 2017, I had an external antenna for my AT&T hotspot (not a booster, just an antenna) and I recall getting better AT&T performance.