John Muir Day is a holiday Celebrated in California on April twenty-first.

The Governor annually shall proclaim April 21st to be 'John Muir Day'
- California Government Code Section 6714.

... All public schools and educational institutions are encouraged to observe... April 21 of each year as John Muir Day... and to conduct suitable commemorative exercises ... stressing the importance that an ecologically sound natural environment plays in the quality of life for all of us, and emphasizing John Muir's significant contributions to the fostering of that awareness and the indelible mark he left on the State of California.
- California Education Code Section 37222 (a)(2) and (b)(2).