How about in the middle somewhere, like Colorado? Kind of evens it up for all four corners. Telluride comes to mind.
http://www.telluride-co.gov/
Camping: http://www.telluride-co.gov/index.aspx?nid=181
Or further south west at Mesa Verde:http://www.nationalparkreservations....Fc57Qgod_EsAMw