I've never been out to the Wildhorse Sanctuary, though it's somewhere on my to-do list. Unfortunately, I don't know very much about it, but sounds like it could be pretty cool. On that subject, you may also want to do the Wildlife Loop in Custer State Park. You probably won't see any mustangs (except perhaps my '97 Mustang ), but you'll usually see Buffalo, deer, antelope, and the wild mules that hang out there. Anyway, here are a few of my favorite haunts:
It's pretty close to Hill City. Just go south down Main Street and head out of town (around 5 miles). Go past the turn at the traffic light for Mt. Rushmore, and it's the very next left. I'm pretty sure there's a sign that says "Sylvan Lake". Just keep following the mountain road (it's a really pretty drive) until you get to the sign for Sylvan Lake (it will be a left-hand turn). You have to pay to get in, but it's worth it. (or you can go on Sunday, when they generally don't have anyone manning the entrance). Great place for a picnic too.
Sylvan Lake Directions
You may have already seen this on my website, but. . .
It will be pretty apparent where the shot was taken when you get there. I climbed up on some of the rocks to get this particular shots, but there are plenty of other locations that don't require any bouldering. I think early morning is the best time for shots of the lake (that's when this one was taken), but you can get good shots in the evening too.
And I know you weren't planning on doing any serious hiking, but here's what you're missing at the top of the Harney Peak trail:
I just love how this mountain seems to rise from out of nowhere. In that way, it reminds me a little of Devils Tower (which you may want to stop by and see if you're going to be coming to South Dakota from the west).
A great place from which to shoot Bear Butte is across the lake in the photo below (OK, it looks more like a lake when it's not frozen). I'm assuming you'll be going through Sturgis, up SR 79. Before you make the right turn off 79 heading into Bear Butte, there will be a dirt road (it may be paved in the very beginning) to your left just prior to the lake. If you take this road all the way around to the west side of the lake, it's a great location to shoot the mountain.
This was an early morning shot (and fairly overcast to the east), but the sunrise is almost 90 degrees off from the viewing angle, so the mountain will look pretty similar from here morning or evening.
For this shot, I was on some back road off to the North/Northwest of the mountain. I was pretty much wandering aimlessly, so I can't tell you exactly where I was.
If you hit Bridal Veil Falls, continue down the road to Roughlock Falls. Just take a right at the Spearfish Canyon lodge and continue down a dirt road until you get to the falls. Roughlock Falls aren't as big, but I think it's far nicer than Bridal Veil. These isn't my best picture, but it's one of the few summer shots I have.
This one's taken from the viewing area just past the falls. I used a monopod and leaned it against the railing, so the camera was actually past the railing. Otherwise, there's too much foliage in the way to get a good shot.
If you're up for a little more walking, there's a trail that continues past the lower viewing area to the parking lot just past the Lodge. It's probably about a half mile one way, and leads down the river. This was obviously a Fall shot, but you get the idea:
They're about 45 minutes east of Rapid City, just across from Wall Drug. If you don't know what Wall Drug is, don't worry. You'll start seeing the signs while you're still 500 miles away. Anyway, Wall Drug is mostly a disappointment, but the Badlands are a pretty interesting, alien-like landscape that looks very out of place in the middle of the South Dakota Plains. Very little walking is required to see some really cool landscapes. These was taken right from the side of the road at sunset. Once again, I was wandering pretty aimlessly, so probably couldn't find the location of this shot on a map, but if you have a GPS or Google Earth, here are the coordinates: N43-47.077 W102-01.056.