[Illustration: Denver and Rio Grande Railway Entering the Portals of the Grand River Cañon, Col.] Where the rocks close in together, as in some of the cañons of our Southwest, the railway curves about them and finds its way often where one would hardly suppose a decent wagon road could be built. The portals of the Grand River Cañon, as here shown, present such a line, passing through narrow gateways of rock rising precipitously on either side to enormous heights. When such a cañon or a narrow valley directly crosses the line of the road, it must be spanned by a bridge or viaduct. The Kentucky River Bridge, shown below, is an instance. The Verrugas Bridge, on the Lima and Oroya Railroad in Peru, is another. This bridge is at an elevation of 5,836 feet above sea-level. It crosses a ravine at the bottom of which is a small stream. The bridge is 575 feet long, in four spans, and is supported by iron towers, the central one of which is 252 feet in height. The construction was accomplished entirely from above, the material all having been delivered at the top of the ravine, and the erection was made by lowering each piece to its position. This was done by the use of two wire-rope cables, suspended across the ravine from temporary towers at each end of the bridge. [Illustration: The Kentucky River Cantilever, on the Cincinnati Southern Railway.] On the line of the same Oroya Railroad is a striking example of the difficulties encountered in such mountain country and of the method by which they have been overcome. A tunnel reaches a narrow gorge, a truss is thrown across, and the tunnel continued. Nature's wildest scenery, the deep ravine, the mountain cliffs, and the graceful truss carrying the locomotive and train safely over what would seem an impossible pass, here combine to give a vivid illustration of an engineering feat. [Illustration: Truss over Ravine, and Tunnel, Oroya Railroad, Peru.]