Mount Rushmore National Memorial, Keystone See the iconic 60-foot faces from several viewing platforms or walk to the sculpture's base with a ranger. Free sculpture workshops and sculptor's studio talks also are available, plus a heritage village and kids' exploration area. Note that although admission is free, you do pay to park.
Falls Park, Sioux Falls Walkways, picnic areas and six viewing areas dot 121 acres overlooking the triple waterfalls of the Big Sioux River, known to the Sioux as Laughing Waters. A five-story observation tower provides sweeping views of the falls and city. A visitors center on the tower's main floor offers Sioux Falls travel information and souvenirs. Free nightly sound and laser light shows (in season) highlight local history.
Falls Park 
Old Courthouse Museum, Sioux Falls Three floors of regional history exhibits draw visitors to a restored 1800s quartzite building (left) that was once the Minnehaha County Courthouse.
Pettigrew Home and Museum, Sioux Falls Tour the 1889 Queen Anne-style home of South Dakota's first senator, Richard Pettigrew, and learn about life in Sioux Falls of the late 1800s.
Transit Trolley, Sioux Falls A free motorized trolley service roams downtown and links many attractions. You can board at any of the trolley banners downtown and in Falls Park.
Transit Trolley 
The Outdoor Campus, Sioux Falls Indoor displays include dioramas of South Dakota habitats and a 3,000-gallon stream aquarium filled with native fish. Outdoors, you'll find a butterfly garden, a playground and two miles of walking trails that pass through tallgrass prairie and woodlands.
The Outdoor Campus 
The World's Only Corn Palace, Mitchell This colorful, half-block-long landmark arena celebrates the region's agricultural prowess with domes, turrets, minarets and murals, decorated each summer with thousands of bushels of corn, grasses and grains. The original Corn Palace was built in 1892 for early settlers to show the fruits of their harvests; the current structure dates from 1921 and now hosts stage shows and sports events.
South Dakota Air and Space Museum, Black Hills At Ellsworth Air Force Base in Box Elder (east of Rapid City on I-90), the museum's indoor and outdoor displays feature four missiles and 25 historic aircraft, including B-29, B-52 and B-1 bombers as well as fighter jets (left).
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Redlin Art Center, Watertown See more than 150 oil paintings by Terry Redlin, known for his nostalgic works depicting wildlife and Americana. Visitors can also view three videos about Redlin's life and paintings. Outside the main building, walking trails wind through the 30-acre Terry Redlin Conservation Park.
Redlin Art Center