Yosemite National Park development. Ackerson Meadow was originally included in the proposed 1890 park boundary but never acquired by the federal government. On September 7, 2016, the National Park Service accepted the donation of the land, making the meadow the largest addition to Yosemite since 1949. Yosemite National Park is located in the central Sierra Nevada of California. Three wilderness areas are adjacent to Yosemite: the Ansel Adams Wilderness to the southeast, the Hoover Wilderness to the northeast, and the Emigrant Wilderness to the north. The park is roughly the size of the U.S. state of Rhode Island and contains thousands of lakes
Yosemite National Park Starting 20 million years ago (in the Cenozoic) and lasting until 5 million years ago, a now-extinct extension of Cascade Range volcanoes erupted, bringing large amounts of igneous material in the area. These igneous deposits blanketed the region north of the Yosemite region. Volcanic activity persisted past 5 million years BP east of the current park borders in the Mono Lake and Long Valley areas. Starting 10 million years ago, vertical movement along the Sierra fault started to uplift the Sierra Nevada. Subsequent tilting of the Sierra block and the resulting accelerated uplift of the Sierra Nevada increased the gradient