[cyber]

Yes, it was: http://www.leginfo.ca.gov/cgi-bin/displaycode?section=veh&gr... states:

"360. "Highway" is a way or place of whatever nature, publicly maintained and open to the use of the public for purposes of vehicular travel. Highway includes street."

https://www.dmv.ca.gov/portal/dmv/detail/pubs/vctop/vc/d11/c...

"22400. (a) No person shall drive upon a highway at such a slow speed as to impede or block the normal and reasonable movement of traffic, unless the reduced speed is necessary for safe operation, because of a grade, or in compliance with law."

Yes, shocking. (Also, El Camino is a State Route, I'll let you look that one up.)