“Lordamighty, she was a killer!”

So said an elderly member of the Canadian Pacific Railway’s Mountain Division in reference to the perilous stretch of rail that connected the summit of Kicking Horse Pass and the town of Field, 237.5 feet below, before the construction of the Spiral Tunnels.

The steep drop was unimaginatively, though not inaccurately, called “The Big Hill,” and is discussed in an old Canadian Geographical Journal story [Read it here]. At its most severe, it sloped at a 5 degree angle. Incredibly, no passenger trains went off the rails during its 24 years of service. The same can not be said of its work cars. Fidler recounts the story of runaway trains and conductors jumping out of windows to escape them. Some died, some, like the infamous devil-may-care engineer who abandoned protocol to ride his speeding train straight into Field, survived (although that particular individual was promptly fired). By the way, protocol involved turning the train into one of three spur lines.

As “The Big Hill” started to see more traffic, it was decided that a better solution was needed. The engineers had more money and more time than their predecessors, and came up with an idea. It took nine years to bore the spiral tunnels through the two mountains. When completed, it was heralded as the engineering marvel of its time. Today it stands as one of the world’s most interesting examples of grade reduction.