State Route 80 (SR 80) is a long, roughly arc-shaped highway lying in southeastern Arizona. Starting in downtown Benson, the highway serves as the main route through the towns of St. David, Tombstone, Bisbee and Douglas before terminating at the New Mexico state line, becoming New Mexico State Road 80 (NM 80). SR 80 also acts as the national southern terminus of US 191 near Douglas and provides the only connection between the U.S. Highway and its business route in Douglas.
Both SR 80 and NM 80 were once part of U.S. Route 80, which traveled through Arizona between San Diego, California and Savannah, Georgia, starting in 1926. The US 80 designation was retired from this route in 1989 after being made redundant by Interstate 10. Despite being replaced by the Interstate, this segment of old US 80 was not closely paralleled by or reconstructed into I-10, as the Interstate was constructed further north and instead supplants the shorter former route of SR 86 and NM 14.
Route description
State Route 80 (SR 80) begins at an intersection with I-10 Business (4th Street) in Benson near an Amtrak station. The route heads south until it exits the city limit of Benson, where it turns slightly southeast, parallelling the San Pedro River through the southern extent of the San Pedro Valley. At the intersection with Apache Powder Road, SR 80 turns eastward, crossing over the San Pedro River and entering St. David as Patton Street. In St. David, SR 80 turns south as Lee Street. South of St. David, SR 80 continues to parallel the San Pedro River until the highway steers southeast, where the river continues due south. from Just north of Tombstone, SR 80 intersects the eastern terminus of SR 82. While SR 82 heads west towards Nogales, SR 80 continues southeast, before entering Tombstone.
thumb|left|SR 80 between Tombstone and Bisbee, seen towards south.
Southeast of Bisbee, SR 80 approaches the international boundary with Mexico as it nears Douglas. Immediately west of town, SR 80 intersects with the southern terminus of U.S. Route 191, directly north of the old smelter site. Entering town, SR 80 becomes 16th Street, which becomes G Avenue shortly before arriving at an intersection with Pan American Avenue, directly in front of the old railroad station, which currently houses the Douglas Police Department. As US 191 Business does not intersect its parent route, US 191, both routes rely on SR 80 as a direct connection. On November 11, 1926, it became part of the transcontinental highway U.S. Route 80, which ran between San Diego, California and Savannah, Georgia. The road was paved at this time between Douglas and Bisbee as well as a portion south of Tombstone. The remainder of the highway was a gravel road. By 1931, the highway was paved from Bisbee to the New Mexico state line as well as a portion south of Benson and another portion south of Tombstone. By 1934, the only portion of the highway yet to be paved was a section between Tombstone and Bisbee. The entire route had been paved by 1935.
By 1964, most of the US 80 nationwide was being largely replaced or made redundant by Interstate 8, Interstate 10 and Interstate 20. On July 1, 1964, California decommissioned its entire segment of US 80 between San Diego and Yuma. The state of Arizona followed suit in 1977, decommissioning all of US 80 west of I-10 in Benson. This made Benson the western terminus of US 80. Between Benson and Rodeo, New Mexico, I-10 did not directly replace US 80, as the new interstate was constructed over the heavier traveled and shorter route of former Arizona State Route 86 and New Mexico State Road 14. US 80 remained designated east of Benson until 1989, when US 80 was truncated to the Texas state line in Anthony, New Mexico, removing the designation entirely from within the state of Arizona. The designation was further applied to parts of Allen Street and 6th Street in Tombstone along with Old Divide Road/Tombstone Canyon Road as well as Main Street in Bisbee and G Avenue, 10th Street and A Avenue in Douglas. These other roads were also designated as part of US 80 in previous years, but were bypassed before SR 80 was designated. The I-10 Business Loop in Benson was also designated as part of the Historic Route, as the loop between I-10 and SR 80 was part of US 80 before 1989.