This field guide includes five places that tell us about the geologic story of Yosemite.

Learning about Yosemite helps Junior Rangers appreciate the park even more. Geology is the study of how land and rocks were formed. In Yosemite, liquid rock slowly cooled and hardened underground. Over time, this rock rose to the Earth's surface and was eroded by water and ice. Geological change is still happening in Yosemite today, mostly very slowly, with the occasional fast rockfall. Much of why Yosemite is because of its unique rock.