Upper Sioux Agency State Park

Yellow Medicine campground at the Upper Sioux Agency State Park is a lovely campground. Not much shade, but tall grasses and a few trees here and there provide a little bit of privacy. I stayed here one night in June 2017, at Yellow Medicine campground site 28e. 30A electric tested and worked fine. There's some highway noise, but it's not too awful, as the highway isn't traveled too often. I'd say I maybe heard a vehicle every 5-10 minutes when it was busy, otherwise rarely.

There's lots of hiking trails and lookouts here, plenty to do for a few days. It's about 12 minutes to Granite Falls which has some stuff, 40 minutes to Marshall which is a little bigger of a town, or a bit over two hours to get to the Twin Cities metro area.

One thing to keep in mind: there are, I believe, three entrances to things in the park. There's the horse campground, the main entrance, and then the campground entrance. If you're in an RV, make sure you don't continue down the small road in the main area (it's for the viewpoint, not campground) because it might get tough to pass someone (I made this mistake, but it was fine). The campground is a little bit further east.

Cell service at campsite, unboosted:

AT&T - three bars LTE, 107ms ping, 10.51mbps down, 4.12mbps up, plenty reliable

Verizon - one bar 1x extended. On occasion, 3G. Completely unusable. Some parts of the park have LTE.

T-Mobile - two bars LTE - I got 63ms ping, 9mbps down, 0.56mbps up. Though, not quite as reliable as AT&T. On occasion, it faded to three bars extended (E).

The campground was partially wooded but mostly had an open prairie feel. There are three sites with modern teepee tents with a plastic decking floor. All other sites are for rv’s or tents with a few walk in sites as well. The campground has a separate entrance as the main state park and is not staffed. I stayed for a week in mid September and was the only camper there for all but the weekend. There is a nice picnic area along the Minnesota river where the Yellow Medicine river joins and is only a half mile down the park’s gravel road. Apparently the fishing is good there since I watched eagles exploiting the many jumping fish as the two rivers joined. The primary drawback is road noise from Hwy 67 which is on the edge of the park. Since it is a hilly winding road at that point trucks make considerable noise slowing for the turns and powering up the hill. It’s not a highly traveled road so don’t let it stop you from using the park. But it is a factor in the mornings and early evenings. It was a typical MN state park with nice gravel rv pads relatively level and well maintained facilities. Plenty of walking trails and a nice historic area at the main entrance.

We stayed here on an August weekend and had no problem getting a site the day of our stay. I suspect construction on the road to the campground might have played a roll in that. We were at the Yellow Medicine campground. At the site we had there was no trees providing privacy between sites but there was ample space between the campsites to make it feel a bit more private. This didn't just feel like a big dirt parking lot like some state parks. The site we had was also fairly big. The campground was fairly quite. The only real noise was the people across from us who had a whiny baby and a dog who barked constantly when they were gone.
We had a friendly ranger stop by the first night we were there and chatted for a few minutes. We did not use the bathroom so I cannot speak to that. There is no water to fill an RV there and no dump station. We got water and used the dump at memorial park in Granite Falls. The bugs were a bit of an issues. There were a ton of flies and quite a few mosquitoes in the evening. As for cell service the Verizon LTE was spotty. At times it was slow but usable and at other times it was unusable. It seemed highly dependent on where you stood.

This is a Minnesota State Park campground so requires the state park pass. I still paid $28 plus an online $7 fee which is a bit steep for electric only. In 2020, highway construction made it nearly impossible to find. Google refused to try. Reservations are online at the state site. No one was present at the campground entrance kiosk. All the sites are back in. The road in is dirt but pretty smooth. Some sites have electric but none have water or sewer. Water is difficult to access so be sure your tank is full before arriving. I did not see a dump station. The sites are well spaced and generally level. There are nice trails in the area. There is a horse camp nearby so a lot of the trails are marked up by hoof prints. The trails are wide enough for an ATV. I saw a deer on the trail through the woods. The camp is nestled between the Yellow Medicine River and the Minnesota River. I suspect the whole area is a flood plain in the spring but it was nice in the fall. There are some hike in campsites by the Yellow Medicine River. There is one standard park outhouse but no showers that I could find. A lot of people were fishing the river. When the roads are finished it should be a short drive to Granite Falls. The most important reason to visit this site is to learn the history of the Dakota Sioux uprising that started here. There are foundations to important buildings that remain. AT&T coverage is nonexistent inside the camper (unboosted) but improves on the trails.

Very nice SP. Site was secluded and shaded. Rangers were great and helpful. Hiking trails were wide, easy. Bathrooms/Showers (free) were spotless. Planned on canoeing, (Minn and Yellow Medicine Rivers) but found that upstream paddling was not practical for my non-canoeing friend. Plus YM River had many trees across and rocks. For swimming, you should go over to Wood Lake County Park, about 8-10 miles southwest.