We are a Swedish family that would like to take a RV roadtrip for the first time. We have 2 children (8 and 11) and will bring my sisters kids from Sweden (16 and 18) We are planning to go for 3 weeks. We live in Los Angeles and would really want to go to Mount Rushmore. We have thought about Santa Fe, Las Vegas, but are not really sure about a good route that will be fun for the kids. Any suggestions about a time-wise realistic route and interesting stops?