>>485661I can't say the best, but they are up there. Harney Peak is about 7200 feet and the highest point I'm the area, it's also near the Needles Hwy. I don't know if it's open up yet, but if it is when you get hear, check it out.
Spearfish has a whole lot of areas to hike around as well. It offers a lot of day hikes and some of the most scenic views of the area.
If feel obligated to say that you shouldn't free roam out here. People underestimate the vast region and the unforgiving terrain. There are so many established trails that you're better off sticking to. I don't want to hear about some anon from Chicago going missing out here.