On our way from Helena to visit the Terry Badlands WSA to hike the Natural Bridges Trail, we decided to skip driving the interstate, and instead take US HWY 89 (MT-12) on our way east.
Using the dyrt to plan our trip, we saw this campground along the way and thought we'd just pop in to spend the night. I'm really glad we did. It's not reservable online, and in an area that's not heavily traveled, so there were plenty of spaces available. In-fact, there was only one other vehicle spending the night a ways away from us, so it felt like we had it all to ourselves.
We pulled in after dark. It's only a short way off of the highway, so you still hear some minimal road noise. (Max nightly fee is currently $18. With a MT fishing license, only $12, and if you're also over 62, only $5.) I would agree with other reviewers that the mix of day use areas interspersed with paid sites is a little confusing, but we had no trouble finding a spot. (Drive around and explore, you can't really go where you're not supposed to be.) We just headed straight in and landed at spot 14 in "Carl's Cove". Normally, this spot would be right on the water's edge, but the reservoir level was far below normal due to drought this year. The FWP ranger that rolled through at 7:30 am to check fee payment (there is no camp host that I'm aware of) mentioned that there may not even be a reservoir next year if conditions remain the same.
I would still camp here again regardless, for the nighttime sky alone. With no light pollution here, on a clear night like ours, the stars were simply astounding. I have only ever seen that many before on a hike through the Crazy Mountains, which you can see to the south from some campsites. The morning views are pretty and the reservoir was like glass with no wind. We took a nice, long walk in the morning to look at all of the other campsites, but if we'd have had a canoe or kayak with us, a morning paddle would have been just the thing.
P.S. We have T-Mobile and still had two bars of 5G access in this spot.