By. BB

In 1890 Yosemite became a national park.

They recognized Yosemite as a national park because of its history, high cliffs and waterfalls. Its beautiful views take people away when they visit.

The geology of the Yosemite area is characterized by granitic rocks and remnants of older rock. About 10 million years ago, the Sierra Nevada was uplifted and then tilted to form its relatively gentle western slopes and the more dramatic eastern slopes. The uplift increased the steepness of stream and river beds, resulting in formation of deep, narrow canyons. About 1 million years ago, snow and ice accumulated, forming glaciers at the higher alpine meadows that moved down the river valleys. Ice thickness in Yosemite Valley may have reached 4,000 feet (1,200 m) during the early glacial episode. The down slope movement of the ice masses cut and sculpted the U-shaped. The valley that attracts so many visitors to its scenic vistas today.

The rocks of Yosemite are plutonic rocks. Plutonic rocks form deep underground when molten rock cools and solidifies very slowly, allowing large crystals to form. In contrast, volcanic igneous rocks form at the surface when molten rock cools and solidifies quickly, resulting in small crystals. Granite, granodiorite, tonalite, quartz monzonite, and quartz monzodiorite are rocks that are found there.

The whole valley ranges from 3,000 feet below to 13,000 feet over in elevation. It has U-shaped canyons, jagged peaks, rounded domes, waterfalls and moraines. These are all outcomes of glaciations.

Smoking when you get there. Leaving trash when you leave. Polluting the air.

The park covers an area of 761,268 acres (3,080.74 km2) and reaches across the western slopes of the Sierra Nevada mountain chain.

Over 3.7 million people visit Yosemite each year: most spend their time in the seven square miles (18 km2) of Yosemite Valley Designated a World Heritage Site in 1984.

Its scenery gets a lot of people in the summer when its hot and perfect to hike!