The Big Hill on the Canadian Pacific Railway main line in British Columbia, Canada, was the most difficult piece of railway track on the Canadian Pacific Railway's route. It was situated in the rugged Canadian Rockies west of the Continental Divide of the Americas and Kicking Horse Pass. Even though the Big Hill was replaced by the Spiral Tunnels in 1909, the area has long been a challenge to the operation of trains and remains so to this day. Construction To complete the Pacific railway as quickly as possible, a decision was made to delay blasting a lengthy tunnel through Mount Stephen and instead build a temporary line over it. Instead of the desired 2.2% grade (116 feet to the mile) a steep 4.5% (some sources say 4.4%) grade was built in 1884. This was one of the steepest adhesion railway lines anywhere. (4.5% = 1 in 22.22). It descended from Wapta Lake to the base of Mount Stephen, along the Kicking Horse River to a point just west of Field, then rose again to meet the original route. Seen as a temporary solution, this grade was twice the percentage normally allowed for a downhill track. The first construction train to go down the pass ran away off the hill to land in the Kicking Horse River, killing three. The CPR soon added three safety switches (runaways) on the way down to protect against runaway trains. The switches led to short spurs with a sharp reverse upgrade and they were kept in the uphill position until the operator was satisfied that the train descending the grade towards him was not out of control. Speed was restricted to for passenger trains and for freight, and elaborate brake testing was required of trains prior to descending the hill. Nevertheless, disasters occurred with dismaying frequency. Field was created as a work camp solely to accommodate the CPR's need for additional locomotives to be added to trains about to tackle the Big Hill. Here a stone roundhouse with turntable was built at what was first known simply as Third Siding. In December 1884 the CPR renamed it Field after C.W. Field, a Chicago businessman who, the company hoped, might invest in the region after he had visited on a special train they had provided for him. At that time, standard steam locomotives were 4-4-0s, capable enough for the prairies and elsewhere, but of little