Bill from Springfield, IL on 5/19/2024 10:50:28 AM:
There is a nice, paved parking lot next to the trailhead in Deadwood. I parked there for several days and didn't have a problem. I didn't leave any personal items of real value in the vehicle. In this day and age, I'm not sure there is any "safe" place to do that. I did have a fairly expensive KUAT bike rack on my SUV and it was still there when I got back. Of course, YMMV.
I'm not sure if you can park overnight at one of the casinos, or not. Or if they would charge to do so. I suppose one downside of parking at the Trailhead is that people assume you may not be back for a few days. Good luck.