We visited in 2017 on our first SD RV trip. We were in SD a couple of years ago but we didn't visit again. Based on what I've forgotten, it's time to go again. Thanks for adding to what I carried away from the first visit.
I went there in 1979 and then a year ago. It looked almost the same........I'll be long gone before it is even close to being finished. But as they say, all great things take time.....