californias mountain and valleys are parallel to the coast because all along the beach is the san andreas fault where two plates are converging causing the mountains to become taller/higher.
The fault lines :)... Hope I helped
California's mountains and valleys run parallel to the coast because of the movement of tectonic plates, particularly along the San Andreas Fault. This geological activity has caused the uplift of significant mountain ranges like the Sierra Nevada and the Coast Ranges. Over time, erosion and sediment deposition have further shaped the landscape into its current parallel form.
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