South Dakota, home of the Black Hills, Mount Rushmore and the biggest freeway tourist trap there is Wall Drug, in Wall, SD, a must see.  Mount Rushmore is an awesome sight to see first hand, no photo can ever represent that feeling.  Down the road from Rushmore is a work in progress, Crazy Horse monument, definitely a good site to see.  Rushmore area full of attractions and lots of History, including numerous Custer battlefields.