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The second set of geologic events includes various forces that caused the uplift of the Yosemite-area mountains and the surrounding Sierra Nevada. The timing and importance of different episodes of uplift are still uncertain, but geologists have established that a tall mountain range has existed in this location since the formation of the granitic batholith. The major river drainages and layout of the mountains have existed since this time. A more recent uplift event, beginning approximately 10 million years ago, led to a steepening of the mountain range. Hand in hand with uplift, and accentuated when uplift is greatest, is erosion, a slow but continuous process that breaks apart and moves rock from the highest summits toward sea level. Erosion occurs as water and ice flow over the rocks; as the rocks freeze and thaw each year, fracturing them; as animals (and now people) dislodge rocks; and in many other ways. Erosion is what has etched the major river valleys and shaped the peaks.

Third are repeated glaciations beginning just 2 million years ago. The glaciers scoured the landscape, scraping loose rock from the sides of valleys, shaping domes and summits, and polishing the rock. Glaciers did not create Yosemite Valley, but they steepened and smoothed its walls and scoured its base. In Tuolumne Meadows, all but the highest summits were submerged in the ice field, and today visitors can still feel the polished rock, visit endless beautiful lakes, and gaze at the pinnacled summits of the Cathedral Range—all the result of glacial action.