My First Summer in the Sierra is a book by Scottish-American naturalist John Muir, published by Houghton Mifflin in 1911. Based on journal entries from the summer of 1869, when Muir accompanied a shepherd and a flock of sheep into the Sierra Nevada of California, the book records his observations of the landscape, flora, fauna, and geology of the range from the foothills near La Grange to the High Sierra around Tuolumne Meadows.