There are two trails that lead you to Harney Peak. Trail number four leaves from near the Sylvan Lake day-use area and also connects with Little Devil's Tower. Trail number nine is the easiest trail to Harney Peak and also leaves from the Sylvan Lake day-use area. We decided to take Trail number four in case we wanted to also climb to Little Devil's Tower.
The trail starts out on a flat forest bottom and begins to climb after about one mile. We encountered some fellow hikers, who I think were from Spain, who said that they lost the trail and had to turn around. This made us a bit nervous, but we kept on hiking anyway. We never strayed off of the trail and found our way to the summit quite easily.
The hike splits to Little Devil's Tower just after the ascent begins. Trail number four connects with trail number nine for the last mile of the hike to Harney Peak. Though this trail did not compare to the trails we took in the later part of our trip in the Rocky Mountains, I thought it was still quite strenuous. This was until I saw a woman who must have been around 80 years old with a cane at the top of the peak. If she can do it, anyone can!!
As you approach the summit, the climb gets more technical with many rocks and boulders. Just below the peak, the park service has built metal and stone steps to make the climb easier. At the top of the peak is an old stone ranger station that is now used as a lookout point. There were many many small bugs up on the peak, which I could not identify. They didn't bite, but they seemed to stick to everything and everyone. You can climb out a bit further on the peak's stones to see a 360-degree view of the Black Hills.
It took us about 5 hours to complete the trail from start to finish. Make sure you bring enough water, as there are no lakes or streams for water along the trail. Also bring along rain gear, as the weather can change unexpectedly.
From journal Mt. Rushmore, Custer and the Badlands, SD 2004