Figure 11 - YOSEMITE CREEK, NOW AND THEN. Today Yosemite Creek (heavy line) flows over the calley rim to create Upper Yosemite Fall. Before its diversion about 130,000 years ago, Yosemite Creek Flowed down an older channel just to the west (heavy dashed line), from which it cascaded down through the steep ravine that is now the route of the Yosemite Falls train. Also shown is a complex of glacial moraiines as mapped by Matthes (1930).