Interstate 90 At a Glance Distance: 475 miles Trip Length: 2 days Start/Stop: Sioux Falls or Belle Fourche South Dakota’s most traveled road is jam-packed with fun surprises. As you journey across the state, brake for selfies at some of America’s most iconic roadside attractions, from giant jackalopes to a palace made of corn. 26 // #HiFromSD The World’s Only Corn Palace