The Ptarmigan Tunnel was built in 1930 through the Ptarmigan Wall at an elevation of 2,200 m in Glacier National Park. The 76 m manmade tunnel allows hikers to avoid a strenuous climb over very steep terrain between Many Glacier and the Belly River valley. 2 opposing steel jackhammers drilling from either side of the tunnel and a series of 10-hole rounds of dynamite gradually broke through the mountain in less than 3 months.
Listed on the NRHP on 2/13/86.
Tunnels, National Register of Historic Places (NRHP)
Links: en.wikipedia.org
By: kkeps