2 votes

BNSF - Cascade Tunnel


West Portal

BH Photo #136195


Cascade Tunnel, East Portal

On my recent trip to Seattle, Washington, I visited the longest railroad tunnel in the U.S., the Cascade Tunnel, and checked out the action on the East Portal.

Video link posted by Ed Hollowell

Play video on YouTube


Concrete lined tunnel under Cascade Mountains on BNSF Railway (former Great Northern Railway)
King County, Washington, and Chelan County, Washington
Open to traffic
Longest rail tunnnel in the US, finished in 1929 to bypass old tunnel, switchbacks, and 1.57% grade
- A. Guthrie & Co. of St. Paul, Minnesota
- BNSF Railway (BNSF)
- Burlington Northern Railroad (BN)
- Great Northern Railway (GN)
It is the longest railroad tunnel in the United States and was constructed by the Great Northern Railway, being put in service on January 12, 1929. The new tunnel reduced the summit by 501 feet (153 m) (to an altitude of 2,881 feet/878 metres) from the original tunnel, which had suffered problems with fumes, and was itself built to avoid problems caused by heavy winter snowfalls on the original line that had eight switchbacks
Total length: 41,152.0 ft. (7.8 mi.)
Also called
New Cascade Tunnel
Great Northern Railway Cascade Tunnel #15
Approximate latitude, longitude
+47.71532, -121.14522   (decimal degrees)
47°42'55" N, 121°08'43" W   (degrees°minutes'seconds")
Approximate UTM coordinates
10/639115/5286325 (zone/easting/northing)
Quadrangle map:
Inventory number
BH 41926 (Bridgehunter.com ID)

Update Log 

  • December 23, 2015: New photo from Charles Kuehn
  • April 30, 2012: Updated by Luke Harden: Refined builder name.
  • April 30, 2012: Updated by Neil Martel: Added builder
  • April 7, 2012: Updated by Luke Harden: Added category "Great Northern Railway"
  • April 7, 2012: Updated by Neil Martel: Updated alternate name
  • September 9, 2010: New photos from Nathan Morton
  • March 13, 2010: Updated by Ed Hollowell: GPS location
  • March 29, 2009: Added by Nathan Morton


  • Nathan Morton - morton890 [at] yahoo [dot] com
  • Ed Hollowell - erhollowell [at] aol [dot] com
  • Neil Martel
  • Luke
  • Wikipedia - Cascade Tunnel
  • Charles Kuehn