All county highways, once established, shall continue to be county highways until abandoned by order of the board of supervisors of the county in which such highways are situated, by operation of law, or by judgment of a court of competent jurisdiction. No county highway laid out by the board of supervisors as provided in this division, or used and worked as provided in this division, shall be abandoned or cease to be a county highway except as prescribed in this section.
(Enacted by Stats. 1935, Ch. 29.)