The modern American environmental movement took a decisive step forward on May 28, 1892, when John Muir and a circle of like‑minded conservationists formally incorporated the Sierra Club in San Francisco. Guided by Muir’s profound spiritual connection to wild landscapes, the new organization set out to defend the American West’s most threatened treasures — focusing its earliest efforts on the preservation of the Sierra Nevada, Yosemite Valley, and the surrounding high Sierra country.
The founding of the Sierra Club established the first durable blueprint for grassroots environmental activism, helping transform the preservation of public lands from a regional cause into a national civic movement.
