loaded trains was kept to a very easy 0.4% while the northbound ruling grade was only 1.35%. Numerous rock cuts had to be blasted and five tunnels, ranging from , were built where rock cuts were not possible. The heavy-haul nature of this railway required all sections of its mainline, including sidings and yard tracks, to be constructed using very sturdy rail in lengths. Since curves account for 54.3% of the main line, extensive use of flange oilers was needed. The oilers were located every or 250 degrees of curvature, whichever was less. Granite, blasted and removed during construction of the harbour at Port Cartier was crushed and used as ballast on the first of the line, while local pit-run gravel was used for the remainder. Twenty-two bridges were needed for the railway, with the bridge at Milepost 68.5 being the longest () and highest () on the line. The railway also required the construction of 1,524 culverts for drainage. The entire line was equipped with Centralized Traffic Control from the very beginning and the railway has twelve sidings between Port-Cartier and Lac Jeannine, named in alphabetical order from south to north. The siding names are Able, Baker, Charles, Dog, Eva, Fox, Georges, Howe, Item, Jig, Kay, and Love. All sidings are in length except for Fox which is and Love at . Since southbound loaded ore trains never enter the sidings, the south ends of each siding have power switches while the north ends have spring switches. However, both Fox and Love sidings have power switches at both ends. Route From Port-Cartier the railway runs northwest along the Aux Rochers River valley and north along the east shore of Lake Quatre Lieues before running west and then north along the MacDonald River valley beside the proposed Lake Walker National Park as far as Lac Valilée. The railway continues northwest to Lake Bourgeois, and runs northward up the east shore of this lake and then of Grand lac Caotibi, running between this lake and Lake Arthur. It then follows the east shore of Petit lac Caotibi to the Rivière Toulnustouc Nord-Est, and follows this river valley northeast and then north past Lac Cartier. Through almost all of this southern section the railway runs through the Port-Cartier–Sept-Îles Wildlife Reserve. The railway continues to follow the Rivière Toulnustouc Nord-Est north and then northwest, then runs northwest to Petit lac Manicouagan. It follows