Yosemite Valley provides examples of various geologic processes. It formed around 10 million years ago as the Sierra Nevada range uplifted, and glaciers later carved out the valleys. On a hike to Upper Yosemite Falls, the author documented different rock types and geologic features. Granite samples showed igneous intrusion, while talus slopes demonstrated mass wasting. Sediment deposition was seen in ice and conglomerate. Frost wedging and erosion illustrated ongoing weathering processes. Practical applications included a bridge utilizing the valley geology.