California Vehicle Code definition of
Crosswalk
CVC Section 275. "Crosswalk" is either:
(a) That portion of a roadway included within the prolongation or
connection of the boundary lines of sidewalks at intersections where
the intersecting roadways meet at approximately right angles, except
the prolongation of such lines from an alley across a street.
(b) Any portion of a roadway distinctly indicated for pedestrian
crossing by lines or other markings on the surface.
Notwithstanding the foregoing provisions of this section, there
shall not be a crosswalk where local authorities have placed signs
indicating no crossing.