Construction of the Lethbridge Viaduct National Historic Event

Lethbridge, Alberta
Construction of the Lethbridge Viaduct (© Library and Archives Canada / Bibliothèque et Archives Canada / PA-027637)
Construction of the Lethbridge Viaduct
(© Library and Archives Canada / Bibliothèque et Archives Canada / PA-027637)
Address : Lethbridge, Alberta

Recognition Statute: Historic Sites and Monuments Act (R.S.C., 1985, c. H-4)
Designation Date: 2005-08-03

Other Name(s):
  • Construction of the Lethbridge Viaduct  (Designation Name)
Research Report Number: 2004-042, 2003-063

Importance: Highest and largest bridge in Canada; greatly improved the hauling capacity and transit time of trains on the Crow's Nest Pass Railway

Plaque(s)


Existing plaque: Lethbridge Junior Chamber of Commerce Lethbridge, Alberta

This Canadian Pacific Railway viaduct, built between 1907 and 1909 across the Oldman River Valley, was an engineering triumph. More than 1,600 metres long and 95 metres high, this steel structure is the longest and highest of its kind in Canada. The designers and labourers had to overcome daunting technical challenges during construction as a result of harsh conditions such as violent winds, dry soils, and extreme temperatures. By allowing significantly longer trains and shorter transit times, the Lethbridge viaduct greatly increased the capacity of the Crowsnest Pass Route.