The wide-open spaces of the Great Plains roll away to infinity to either side of I-90 in South Dakota . Though the land is more green and fertile east of the Missouri River, vast numbers of high-season visitors speed straight on through to the spectacular southwest, site of the Badlands and the adjacent Black Hills - two of the most dramatic, mysterious and legend-impacted tracts of land in the US. For whites, they encapsulate a wagonload of American notions about heritage and the taming of the West. To Native Americans they are ancient, spiritually resonant places. The science-fiction severity of the Badlands resists fitting into easy tourist tastes. The bigger, more user-friendly Black Hills, home of that most patriotic of icons, Mount Rushmore , have been subjected to greater exploitation (dozens of physical, historical and downright commercial attractions, and the mining of gold and other metals), but encourage more active exploration (via hiking trails, mountain lakes and streams, and scenic highways). Time and Hollywood have mythologized the larger-than-life personalities for whom the Dakota Territory served as a stomping ground: Custer and Crazy Horse battled here for supremacy over the plains, while Wild Bill Hickok and Calamity Jane were denizens of the once-notorious Gold Rush town of Deadwood . On a more contemporary note, Kevin Costner's award-winning Dances with Wolves (1990), shot in the state, boosted South Dakota's tourism image, though Costner's own ambitious development plans for the Black Hills have meant that he himself has fallen foul of the Sioux. Sioux tribes dominated the plains from the eighteenth century, having gradually been pushed westwards from the Great Lakes by the encroaching whites. To these nomadic hunters, unlike the gun-toting Christian settlers and federal politicians, the concept of owning the earth was utterly alien. They fought hard to stay free: the Sioux are the only Indian nation to have defeated the United States in war and forced it to sign a treaty (in 1868) favorable to them. Even so, they were compelled, in the face of a gung-ho gold rush, to relinquish the sacred Black Hills, and ultimately the choice lay between death or confinement on reservations. For decades their history and culture were outlawed; until the 1940s it was illegal to teach or even speak their language, Lakota. More Sioux live on South Dakota's six reservations now than dwelled in the whole state during pioneer days, but their prospects are often grim. Nowhere is the leg-acy of injustice better symbolized than at Wounded Knee , on the Oglala Sioux Pine Ridge Reservation - scene of the infamous 1890 massacre by the US Army, and also of a prolonged "civil disturbance" by the radical American Indian Movement in 1973. Today Native American traditions are celebrated by music, dance and socializing at powwows , held in summer on the reservations; the state tourist office can supply dates and locations. Apart from powwows, South Dakota summers are taken up with historical celebrations, volksmarches (a friendly sort of community walking exercise), ethnic festivals and rodeos. The 200th anniversary of the Lewis and Clark expedition will be celebrated between 2003 and 2006; check for event details. The state has 170 parks and recreation areas for hikers and campers. In winter, downhill skiing is limited to Terry Peak and Deer Mountain outside Lead in the Black Hills; cross-country skiing and snowmobiling are more prevalent.