Ptarmigan Tunnel

Ptarmigan Tunnel - Credit: Wikimedia Commons

The Ptarmigan Tunnel was built in 1930 through the Ptarmigan Wall at an elevation of in Glacier National Park, near Many Glacier, in Montana, US. The manmade tunnel allows hikers to avoid a strenuous climb over very steep terrain between Many Glacier and the Belly River valley. Two opposing steel jackhammers drilling from either side of the tunnel and a series of ten-hole rounds of dynamite gradually broke through the mountain in less than three months. Read more on Wikipedia

type: NRHP
date from: 1930

Source: en.wikipedia.org