A scenic road is a term that is often used to apply to several types of roadways offering visual, historic, and cultural significance. ADOT oversees the designating and planning of 5 types of scenic roads. They are listed below beginning with the easiest type of scenic road to designated and ending with the most difficult scenic road to designate:

Gila - Pinal Scenic Road
Scenic Roads
These roads include a roadway (or segment of a roadway) that offers a memorable visual impression, is free of visual encroachment, and forms a harmonious composite of visual patterns. Scenic roads are the most commonly designated type In Arizona; there are 18 roads designated as Scenic Roads. Some of the more popular Scenic Roads include:
Jerome - Clarkdale - Cottonwood Historic Road
Historic Roads
These roads include a roadway (or segment of a roadway) that offer historical importance to the cultural heritage of the state, nation, or region, contribute to a historical area or exploration/settlement of Arizona, be easily accessible, and uniqueness. This type of scenic road is far less common than designated Scenic Roads. In this state; there are presently two Historic Roads:

Swift Trail Parkway
Parkways
Parkways include a roadway (or segment of a roadway) that meets scenic or historic road criteria, have a one-mile minimum distance between access roads, allow visitor facilities/interpretive areas, and offers controlled access and adjacent development. This type of scenic road, similar to Historic Roads, is far less common than designated Scenic Roads. In this state; there are presently two Parkways:

Sky Island Parkway (Catalina Highway) National Scenic Byway
National Scenic Byways
National Scenic Byways include a roadway (or segment of a
roadway) that has multi-state significance and posses one
or more of the following qualities: scenic, historic, recreational,
cultural, archaeological, or natural. They must be a currently
designated State scenic road, and contain no gaps in continuity,
accommodate bicycles and pedestrians, and have a completed
Corridor Management Plan, In Arizona, there are three National
Scenic Byways:

Red Rock All-American Road
All-American Roads
All-American Roads include a roadway (or segment of a roadway) that has national significance and posses a multiple of the following qualities: scenic, historic, recreational, cultural, archaeological, or natural. They must be a currently designated State scenic road, and contain no gaps in continuity, accommodate bicycles, pedestrians and scenic pullouts, have a completed and implemented Corridor Management Plan., Lastly, the road must be considered a destination. In Arizona, there are two scenic roads designated as All-American Road: