Mount Roosevelt is a fantastic spot watch the sunset, see numerous prominent peaks in the area and get out of Deadwood after you maybe have spent too much money gambling.
To get to the trailhead for Mt. Roosevelt, you will need to travel about a mile north of Deadwood, on HWY 85, then you will see signs for it near the Lodge of Deadwood, from there you will eventually hit a gravel road and it is about 2.5 miles from the highway. The trailhead has picnic tables, and a vault toilet for amenities.
The trail is very well maintained and prominent! Along the trail you will find historical plaques and area information. The trail forms a loop that is about 0.8 miles long, and is moderate, not challenging at all. Once you get to the top of the hill you will be rewarded with incredible views and you can enhance those views by climbing 24 sandstone steps into the Roosevelt Tower! From the tower you can see numerous prominent peaks in the hills, including Bear Butte, Spearfish Peak, and Crow Peak.