The Sierra Club is a nonprofit organization that promotes environmental conservation. It was founded in 1892 by John Muir and is one of the oldest and largest environmental organizations in the United States. The organization has over 3.8 million members and supporters and is dedicated to protecting the planet's natural resources and wildlife. The Sierra Club engages in a variety of activities, including lobbying for environmental legislation, organizing outdoor activities, and publishing a magazine. The organization is headquartered in Oakland, California.