Air-Tour Grand Canyon, Rocky Mt, Great Plains, Ctr Lowland, Los Angeles - Chicago,

In US, Only about 5% of the land has cities, towns, or roads, 47% of the USA remains uninhabited. Especially in the western half of the country which is mostly forest or mountainous with some desert in the southwest.
Colorado in Spain means Color-Red, Colorado Plateau is the most featured Plateau with 2 billions years characteristic deposit exposed.