The Arizona Copper No. 7, or more affectionately named, "Rattlesnake" is a 0-4-0T steam locomotive built by the H. K. Porter Company of Pittsburgh, Pennsylvania in 1896 for the Arizona Copper Company of Morenci, AZ.
The locomotive once pulled ore trains from the Metcalf mines until it was retired in 1922 when the Coronado Railroad ceased operations. In 1923 the locomotive along with two other engines (Arizona Copper No. 2 and No. 5), were left abandoned on top of a steep 1,200 foot Coronado mountain incline for several decades.
No. 7's boiler
The three abandoned locomotives were found and rescued in late 1990. No. 7 was donated to the "Museum of Discovery" in 1993, now the EAC Discovery Park Campus. During its time at EAC, the locomotive was disassembled in a effort to restore it but those plans fell through. In 2021, EAC donated the disassembled locomotive to the Arizona Railway Museum in Chandler, with the promise of being restored and displayed for visitors to learn about its history.