US 80/US 89 continued south on current SR 77 across the Pima County line where the highway becomes Oracle Road. Both highways passed through the town of Oro Valley on the western side of the Santa Catalina Mountains before crossing the El Rillito river into Tucson. Where SR 77 turns west onto Miracle Mile was where US 80 and US 89 met SR 84. This intersection was formerly a large traffic circle. South of this point, Oracle Road was once part of Tucson's Miracle Mile District, a former bustling business district lined with historic motels and iconic structures. US 80, US 89 and SR 84 continued south on Oracle Road, then east at another large traffic circle on to Drachman Street through the Miracle Mile District, passing the iconic Tucson Inn before reaching the end of the Miracle Mile at Stone Avenue.

The three highways proceeded to curve south onto Stone Avenue, passing the 1936 Art Deco-styled Old Pueblo Service Station before taking the Stone Avenue Underpass, a decorative Gothic Style 1939 underpass, to cross the Southern Pacific Railroad into downtown. US 80, US 89 and SR 84 continued on Stone Avenue through downtown to the Five Points intersection at 18th Street and 6th Avenue, where Stone ended. The highways from this point used 6th Avenue to continue south through the enclave of South Tucson, passing a few more historic 1930s era motels. Sixth Avenue met Benson Highway at an intersection just north of the Southern Arizona Veterans Affairs Hospital. Today, this part of Benson Highway is now I-10. SR 84 ended at this intersection, while US 89 continued south on 6th Avenue to Tubac and Nogales. US 80 turned east onto present-day I-10, passing the historic Old Spanish Trail Inn right before curving southeast onto Benson Highway. Benson Highway has a row of neon-signed motels that stretch southeast out of Tucson towards Vail, including the iconic Spanish Trail Inn, which now stands partially abandoned. US 80 then continued southeast on Benson Highway, exiting Tucson.

Tucson to the New Mexico state line

At Valencia Road, US 80 continued towards Vail along present-day I-10, passing the Triple T Truck Stop at Craycroft Road along the way. Near Vail, US 80 diverged from I-10 onto the north frontage road, crossing a decorative wash bridge. Going south of Vail past the northern terminus of SR 83, US 80 went northeast through small foothills on Marsh Station Road, crossing Ciénega Creek over the historic 1921 Ciénega Bridge. The highway then arrived in the small town of Pantano. Today, Pantano is a ghost town, with few structures still standing. US 80 continued southeast on Marsh Station Road, returning to the routing of I-10, then crossed the Cochise County line. Just across the county line, US 80 made a small curve onto Titan Drive, crossing under the now-abandoned El Paso and Southwestern Railroad before returning once again to the route of I-10. Arriving in Benson, US 80 headed east onto 4th Street (now I-10 Business) through the town center. US 80 met the western terminus of the eastern section of SR 86 at a 1941 interchange/underpass complex. SR 86 continued east on I-10 Business and I-10 towards Willcox and New Mexico, while US 80 turned south on what is now SR 80. US 80 then passed through St. David as Patton Street and Lee Street, heading towards Tombstone.

Allen Street (former US 80) in Tombstone

Passing the eastern terminus of SR 82 near Fairbank, US 80 came into Tombstone on SR 80 and Sumner Street. At Fremont Street, US 80 continued southwest for one block to Allen Street, then continued southeast on Allen through the heart of Tombstone, passing the O.K. Corral and the site of the infamous gunfight. The highway turned northeast on to 6th Street for one block, then turned southeast on to Fremont Street. US 80 exited Tombstone on Fremont Street, before continuing southeast on SR 80, passing the eastern terminus of SR 90. At the intersection with Old Divide Road, US 80 headed south over Mule Pass on the winding mountain road over what was once believed to be the Continental Divide. On the other side of the pass, US 80 then curved east onto Tombstone Canyon Road, entering the mining town of Bisbee.

The Phelps Dodge smelter in Douglas, during operation in 1944

Entering downtown Bisbee, US 80 became Main Street, winding its way past the historic Copper Queen Hotel. On the east side of downtown, the highway continued east on SR 80 at the Copper Queen Mine and skirted the edge of the massive Lavender Pit mine, curving onto Erie Street and entering downtown Lowell. US 80 then passed under the El Paso and Southwestern Railroad, meeting SR 92 at its eastern terminus before running northeast of Warren through Grace Corner towards the Mexican border. Near the border, US 80 turned directly east, meeting the southern terminus of US 66 before crossing under the El Paso and Southwestern Railroad again, heading into Douglas, Arizona.