Most of the backcountry in Glacier National Park is close to untouched, which makes the Ptarmigan Tunnel all the more interesting. The 250-foot long tunnel was built in 1930 and saves hikers what would otherwise be a serious climb as they link Many Glacier to the remote Belly River. Coming from the Many Glacier side the tunnel is not visible -- only a trail snaking up the mountain which mysteriously seems to disappear midway. Wind rushes through the tunnel and enterprising squirrels will snatch any food left unattended. On the far side the trail is dramatically hacked into a cliffside as it descends to the north. The tunnel is difficult to access in winter and normally open only between July and October; check with the ranger in Many Glacier for current updates.