Yosemite National Park, located in the Sierra Nevada mountains of California, last had volcanic activity approximately 5 million years ago in the Mono Lake and Long Valley areas of the park. Granite formations occurred due to the volcanic activity and uplift from movement of tectonic plates in the region.
Granite formations are common throughout Yosemite and surrounding regions. The area's history is full of volcanic activity, upheaval of tectonic plates, glaciers and erosion, all of which contributed to the rock formations found in the area. These geologic conditions took place over 100 million years, with glaciers, uplift and erosion being the primary causes of the landscape today.