Blackwell campground is very nice - surprisingly well-maintained with unique sites, many of which are large and private.  Some have large lawn areas as well as nice wood-chip pads, while others are mostly gravel.  All look very level.  Bathrooms and shower house are clean and also well maintained and water is available at quite a few spots.  The main road throughout the camp is mostly large gravel - keep that in mind if you're walking to the shower house, your flip-flop shower shoes are probably not going to be comfortable! 

Note that you have to drive over 5 speed bumps throughout the preserve to get to the campground.  The preserve itself is large and one of the best in the area, with boat rentals, hiking trails, picnic areas, and even an archery range.   It's in the middle of a suburban area with lots to do nearby, so you'll get great cell signal and unfortunately lots of road noise.

Beautiful shady campground with large private sites.  Sites 111 - 139 are more open with less privacy, but they have lake views and are near the concession stand and boat launch.  Sites in the other loops are all very shaded and private.  The shower houses were clean and large, in good repair.  The park itself has great hiking trails and many nice picnic spots, boat and kayak rentals.

Site 16 is mostly sun.

Site 18 is nice but has no AT&T signal (it's hit or miss here).

Site 24 is very large with an additional tent pad and good AT&T signal.

Sites 63 & 64 can smell the pit toilets, avoid!

None of the sites we saw had a grill over the fire pit, so be prepared for that.

I'll start by saying that I like privacy and quiet and nature when I camp, otherwise I'd be staying in a hotel.  But we were looking to get away for a weekend during the COVID times, and site 65E was the only powered site available for that weekend in all of the Wisconsin state parks, so we decided to go for it.  If you're the social type with active young kids, that spot is perfect - it backs up to a large open field with cool playground equipment and has a trail to the field right next to the camper.  You're also right next to the water faucet (plenty of people will stop to chat there) and across the street from the pit toilets. It's a VERY busy site.  If I return, I'll pick site 107E, which is extremely private and far from everything.  In general, the 100+ sites looked to be on the quiet, private side of the campground, although not all had power.  Some of the unpowered sites. 69-79, had great lake views and were surprisingly spacious, although a hiking trail is between them and the lake.  In late July, the loop starting with site 41 is absolutely teeming with ripe blackberries.

The shower houses have little notes on them apologizing for their state and saying they're scheduled for an overhaul soon because they're almost 50 years old.  So definitely go in with low expectations.  Few of the stalls for the flush toilets had working doors, and while the showers themselves worked ok, there were no hooks, shelves, or anywhere inside to place your belongings.  My shower bag randomly has a suction cup and I optimistically tried to use it to stick to the pink tile wall, but even that didn't work.  Such is life.  Mirrors above the sinks were the polished metal type.

The pit toilets in the campsite have two stalls in each, so don't be surprised if you end up with a buddy.

The hiking trails around the park are great, nice long loops, and the ranger/park employee at the check-in area was very nice and knowledgable.  We rented a kayak and paddled around the lake for a couple of hours - single and double kayaks as well as canoes are available for rent for the day.  There was a rocky beach with so many signs up warning about different types of algae that we weren't sure if it was safe to swim or not, but definitely too gross to regardless.  I didn't see anyone else in the water either.  

If it's a clear night, the field with the playground equipment is a great place to sit and stargaze, as the park gets very dark at night.  We were even able to catch a few meteors!

We've stayed at this campground twice so far and enjoyed it both times.  Our first visit was in April before they turned the water on (we were prepared for that).  The campground was mostly empty and I don't believe the hosts were there for the season yet, but it was very quiet and peaceful.  The shower house was closed until May but the pit toilets were open and still reasonably clean.  The hiking trails are great (although be prepared for mud) and one even takes you right under an eagle nest.  Bald eagles are visible on the river, and since the campground is right next to a Dark Sky Park, stargazing is amazing if you have good weather.  

Our second visit was in August for the Perseid meteor shower and a local expert came to give a talk and there was a meteor viewing party of sorts, so that was very interesting.  The camp was entirely full and got pretty loud Saturday night, but otherwise wasn't bad.  At one site, people had squeezed a large camper, two large tents, and five cars on it, despite the limits - I felt bad for their neighbors!  We also had a lot of rain that weekend and one of the pit toilets appeared to have a problem because it smelled very strongly - the people in the sites nearest to it, 21 and 39, probably had a rough weekend.  

There are several fishing ponds around the campground and a small swimming area with a beach, playground, mini library, and shower house.  The shower house is older but decent and clean.  The showers themselves have a lot of hooks inside to hang your things, and the accessible shower was very thoughtful with a bench and handheld shower head (not like some which have regular showers, just bigger). 

Some of the sites are very private, others are closer together.  42 - 47 had a lot of vegetation between them and were very private. I believe sites 34 and 27 could be great buddy sites. Site 25 has a trail that leads to the back row of sites (and no one behind it.)

The alphabetical sites are a little tighter, smaller, and with less privacy.

The water faucet/pump in the middle of the back row is broken and has been removed, although it is still on the map.

AT&T cell reception is good at any of the sites.

We stayed for a long weekend at the end of June when the campground was almost completely full.  The camp hosts were lovely!  Since we did not have reservations ahead of time, we chose from the walk-in sites, which I believe are the first two loops closest to the entrance.  Those sites, 5-46E, are very different from the rest of the campground.  They're shaded by huge (by Illinois standards) pine trees and there is no privacy screen of vegetation between the sites, although they're nicely spaced out.  The middle part of the campground has smaller trees and grassy lawns, still pretty open, while the outer loops are closely packed.  With the outer loops, you won't have any cell signal, but you probably won't hear the trains, either.  

The park: beautiful area with lots of interesting wildlife (quite a few snakes so be aware if that's not your thing) and great views of the river.  I found the hiking trails to be significantly harder than advertised as they all start with a steep climb up the bluffs, but the views at the top were rewarding.  Some viewing areas are accessible by car.  There's not much to do in the surrounding towns, but this is a great stopping point if you're on a trip.

Site 11: electric with water nearby, close to the (very clean) pit toilets.  Although there is a camp store and parking lot directly behind this site, the store was closed and looked like it was going to stay that way, so there was no additional noise.  Being up front in the campground, you're closer to both the road and the train tracks, so be prepared for noise from that - but at least the AT&T cell signal was good!  The tall pines were great for providing shade and still allowing a nice breeze, but you WILL get sap on everything.  

The shower houses:  the shower houses were some of the nicest we've encountered while camping - hot water immediately, hooks to hang your things, very clean, flush toilets and real mirrors.  There are several shower houses throughout the campground.

A note about the pit toilets - the ones closest to the camp store (and I assume the rest, but did not verify) had the type of light that turns on VERY slowly, so if you're going at night definitely bring a flashlight! In addition, there was always some sort of critter in there - toad, fox snake, etc.  I found it entertaining but my mother in law probably would have straight up died had she come along!