-The mine opened in 1877 and closed in 1975, when Phelps Dodge stopped mining operations in Bisbee
-It reopened in 1976 as a tour for visitors
-The mine has seven levels with 143 miles of passageways
-The mine's ore-body is 23% copper, which is a very high grade
-The mineralization is high-grade copper carbonates with minor lead zinc and carbonates