Business Loop 8 in Alpine spanned from I-8 exit 30 to exit 33 and was mostly former US 80 along Alpine Drive.
El Centro loop
Business Loop Interstate 8 is a business loop route that diverges from Interstate 8 in El Centro, California, to pass through the downtown area. Interstate 8 Business originates and terminates with I-8 and acts as a direct link to El Centro as I-8 bypasses the downtown area. The I-8 Bus. path through El Centro traces roughly three sides of a rectangle with I-8 constituting the fourth side. I-8 Bus. begins at its western terminus with I-8 by going north along Imperial Avenue. When I-8 Bus. reaches the intersection of Adams Avenue it turns east along that road. Along this stretch, I-8 Bus. is joined by State Route 86 which approaches from the north along Imperial Avenue, and by Imperial County Route S80 which approaches from the west along Adams Avenue. The three routes continue joined as Adams Avenue ends and turns south along Fourth Avenue where S80 then turns to continue east. I-8 Bus. and SR 86 continue south running concurrent until I-8 Bus. reaches its eastern terminus with I-8. Only the portion of I-8 Bus. that runs concurrently with SR-86 is maintained by the state. Along its concurrency with SR-86, I-8 Bus. is designated as part of the Juan Bautista de Anza National Historic Trail. Major intersections
Winterhaven–Yuma loop
Business Loop 8 begins at an interchange with I-8 and Winterhaven Drive inWinterhaven, California. The loop continues east, paralleling I-8 to the north and running concurrently with CR S24. I-8 Bus. then goes through downtown Winterhaven before CR S24 continues east and I-8 Bus. continues south, crossing I-8 again as well as the Colorado River into Yuma, Arizona. Passing to the west of Yuma Quartermaster Depot State Historic Park, I-8 BL goes through downtown Yuma as Fourth Avenue, intersecting US 95 after several blocks. The business loop curves to the east as 32nd Street, passing along the north side of Yuma International Airport and the south side of the Yuma Conservation Garden. East of the airport, I-8 BL passes through less-developed areas of eastern Yuma before ending at I-8. It is one of very few Interstate business loops that is interstate in the sense of crossing a state line. The Arizona segment of the business loop is also a section of Historic US 80. Major intersections
State Business Route 8 begins at an interchange with I-8 west of Gila Bend before passing under the freeway, continuing east and merging with SR 85 at a truck stop. As Pima Street, the two highways continue through downtown Gila Bend before I-8 BL turns south away from S 85 as Butterfield Trail and ending at I-8 at a diamond interchange. ;Major intersections
