the Mintlaw bridge, 1911
1911: the construction of a steel trestle across the Red Deer River, 644m long, 33m high. Like an east-west pipeline, it was resource-related; the Alberta Central Railway was meant to carry coal from the coal fields near Nordegg and Rocky Mountain House to Vancouver. It went bankrupt and the line was leased to the CPR for 999 years. What a curious concept that is, leasing for a millenium.
The line was underused (WWI, the depression, WWII and the discovery of oil in Alberta changed the energy landscape somewhat) and eventually abandoned in 1983, but the Mintlaw trestle bridge still stands. It's a grand picture, the construction of the bridge. The bridge is its own construction scaffolding.