Muni is celebrating the 50th anniversary of its beloved “Worm” logo, which was designed by Walter Landor, founder of the esteemed Landor Associates who also worked with big name clients such as Levi’s, Fed Ex, and Coca-Cola.

The Muni Store website describes the design details of the Worm logo:

The intertwined "M" and arrow, rendered in distinctive red orange, cleverly symbolize movement and interconnectedness. Many look at this mark as a symbolic reference to the streets, hills and valleys of San Francisco.

Prior to the Worm, the logo has undergone several transformations over the past century. The earliest design featured “Municipal Railway” in gold lettering on streetcars in 1913. In 1919, the first true logo, the circular “O’Shaughnessy” badge was introduced, featuring “S.F.” and “Municipal Railway,” which lasted for nearly 50 years with variations in color schemes.

Following the SFMTA’s formation in 1999, there was debate over replacing the “Worm” with a new MTA logo, but the classic design prevailed. And we wouldn't have it any other way.

Previously: Muni Launches Online Store Full of Muni-Branded T-Shirts, Hats, Hoodies, Mugs, and More