|The United States' longest railroad tunnel is the bore throught the crest of Stevens Pass. Here a westbound emerges into the morning sunlight after cruising through almost eight miles of gloom. This is the west portal of Cascade tunnel. This end has remained almost unchanged for over 70 years. The east portal however, where the fan house for ventilation is built has had more than one full facelift not to mention an increase in tunnel length of almost 20 feet.