Cal. Gov. Code § 38302

The city legislative body may grant franchises for the building and operation of railroads from any point in, or at the exterior boundary of, the city to, in, or through city-owned parks situated outside the city limits, in the manner and to the extent that it may for street railroads within the city limits. Any such franchise shall contain a condition that the railroad fare does not exceed five cents ($0.05) for a single trip.