Keystone  has something for every visitor. There are kitchy souvenir shops right next door to shops featuring fine art specialty gifts. As is common in most seasonal tourist areas, shops can change from year to year and sometimes the best way to find a treasure is to park the car and go walking. Off-season, hours can be fairly whimsical, so it might not be a bad idea to call first if you are planning on visiting a specific shop.
Look for funky specialty shops in the historic center of Keystone off of Highway 40 east of U.S. 16A. Along 16A (the main road to Mount Rushmore), there are two distinct shopping districts. The first, called “the strip,” is near the 1880 Train station  at the junction of U.S. 16A and Highway 40. Farther south and closer to Mount Rushmore  is the Keystone Mall. Less than a mile apart, both locations are filled with shops and places to eat.
The Rock Shed (515 First St., 605/666-4813, www.therockshed.com , Apr.–Oct. Mon.–Sat. 8 a.m.–5 p.m., Sun. 1–4 p.m., off-season Mon.–Fri. 9 a.m.–5 p.m., closed Sat.–Sun.) is one of the enduring shopping spots in Keystone. In business since 1968, the store specializes in rocks, gemstones, fossils, and minerals. Located in the historic center of Keystone, the store also maintains an active and detailed catalog of the unique rocks and minerals available on their website.
Located a few miles outside of town on the Old Hill City Road, Black Hills Glass Blowers (909 Old Hill City Rd., 605/666-4542, www.blackhillsglassblowers.com , mid-May–late Sept. Mon.–Sat. 9 a.m.–5 p.m., Sun. 11 a.m.–5 p.m., off-season by appointment) is a unique studio and retail shop where beautiful wine glasses, water glasses, plates, vases, and glass figurines are created as you watch. Artisans Peter Hopkins and Gail Damin have been working together for over 25 years and opened their studio and shop in Keystone in 1991. Each of them is proficient at creating both blown glass (off-hand work) and lamp-worked pieces. While there are no scheduled demonstrations of glass work, one of them is likely to be working any time the shop is open.
One of the most popular stops in town is the Rushmore Mountain Taffy Shop (203 Winter St., 605/666-4430, www.rushmoremountaintaffy.com , May–Sept. daily 8 a.m.–10 p.m., off-season daily 8 a.m.–4 p.m. or 6 p.m.)—no vacation community boardwalk is complete without a taffy shop. I’m not sure what makes the sticky confection so irresistible, but it might be the many choices of exotic flavors. Strawberry cheesecake, peach, and chocolate cherry sound interesting, but jalapeno taffy sounds like something only a 10-year-old could love. The most popular flavors include cinnamon and huckleberry.
Old Fashioned Fudge (117 Winter St., 605/666-4675, www.turtletown.com , June–Aug. daily 7:30 a.m.–10 p.m., May and Sept.–Oct. daily 8 a.m.–7 p.m., closed in off-season) has been located on the strip in Keystone  since 1977. The store owners have expanded the initial offerings from simple fudge to include handmade fine chocolates, ice cream, and a coffee bar. Wherever you go for lunch, be sure to stop here for dessert. With nine different varieties of fudge alone, truffles, caramels, divinity, and toffee, there is something sweet for everyone.
The Good Tyme Photo Shop (804 U.S. 16A, 605/666-4619, May–Sept. daily 9 a.m.–9 p.m., closed in off-season) is a great place to get something unusual for a souvenir. Take a family photo and bring the Old West home. The shop offers 11 different sets, including an Old West bar, a jailhouse, sod house, Victorian parlor, a buffalo scene, and a bath tub, all of which are Western or Victorian in nature. And then, just for something different, you can pose in front of a 1920s car and dress like Bonnie and Clyde.