Claim: The Mount Macdonald Tunnel supplements the Connaught Tunnel.

The Mount Macdonald Tunnel , located in the vicinity of Rogers Pass in the Selkirk Mountains of British Columbia , Canada , is a railway tunnel constructed through Mount Macdonald by the Canadian Pacific Railway -LRB- CPR -RRB- .   The Mount Macdonald Tunnel supplements the nearby Connaught Tunnel that the CPR opened in 1916 . Construction commenced in 1984 , and the first revenue train passed through in 1988 . Official inauguration took place May 4 , 1989 . At 14.7 km -LRB- 9.1 miles -RRB- , the Mount Macdonald tunnel is possibly the second-longest -LRB- after Cuajone-El Sargento tunnel in Peru -RRB- railway tunnel in the Americas , rather than the longest . This is suggested because while the source -LRB- an unverified photographer -RRB- says that the Peruvian tunnel is the longest , Google Earth measuring tools show Mount Macdonald Tunnel -LRB- east portal location is 51 ° 20 ' 26.98 '' N , 117 ° 25 ' 27.96 '' W , west portal is 51 ° 15 ' 26.14 '' N , 117 ° 35 ' 02.26 '' W -RRB- as being 48,822 feet -LRB- 14,881 meters -RRB- in length , while the Peruvian tunnel -LRB- north portal is 17 ° 06 ' 28.4 '' S , 70 ° 40 ' 44.64 '' W , south portal is 17 ° 14 ' 15.96 '' S , 70 ° 38 ' 59.07 '' W -RRB- is measured as being 48,263 feet -LRB- 14,710 meters -RRB- long , making the Peruvian tunnel 559 feet -LRB- 171 meters -RRB- shorter . Since both the accuracy of Google Earth 's measurement tools and the source of this photo are unverified , additional verification is needed to determine which of the 2 tunnels is actually longer .   The tunnel and the associated grade revision on the eastern approach to the pass lead to a significantly gentler slope for westbound trains . The new track separates from the old grade at Rogers -LRB- approximately 25 km east of the pass -RRB- and climbs at a lower grade . Numerous new bridges and the 1.9 km Mount Shaughnessy Tunnel were required to reach the pass . The Mount Macdonald Tunnel is 91 m lower than the Connaught Tunnel . On the west side of the pass , the Mount Macdonald Tunnel track rejoins the older line 5.5 km west of the Connaught Tunnel .   The reduction in the westbound ruling grades allowed the Canadian Pacific Railway to remove the pusher locomotives that had been required on the Connaught Tunnel route . This was especially important for the unit coal trains from the Crowsnest Pass area destined for Asian markets through the port of Vancouver , British Columbia . Trains now predominantly travel east through the Connaught Tunnel and west through the Mount Macdonald Tunnel .