National Geographic : 1914 Aug
Photo by Kolb Brothers TIHE HIGHEST SHEER WALLS IN THE GRAND CANYON The inner gorge is about 3,000 feet deep. The upper walls tower about 4,500 feet above the river. In these narrow sections the floods sometimes rise Ioo feet above the low-water mark. It was very cold while going through this section. Little or no sun reaches the bottom of these canyons in January, except where the course varies from its east to west direction. Cold winds would sweep down from the snow-covered cliffs above and we were constantly shifting about to keep warm.