Sts. & Hy. Code, § 411

(a) Route 111 is from:

(1) The international border south of Calexico to Route 78 near Brawley, passing east of Heber.

(2) Route 78 near Brawley to Route 86 via the north shore of the Salton Sea.

(3) The western city limits of Cathedral City to Route 10 near Whitewater.

(b) The relinquished former portions of Route 111 within the unincorporated area of the County of Riverside and the Cities of Cathedral City, Coachella, Indian Wells, Indio, La Quinta, Palm Desert, and Rancho Mirage are not state highways and are not eligible for adoption under Section 81. For the relinquished former portions of Route 111, the County of Riverside and the Cities of Cathedral City, Coachella, Indian Wells, Indio, La Quinta, and Palm Desert, as applicable, shall maintain within their respective jurisdictions signs directing motorists to the continuation of Route 111 and shall ensure the continuity of traffic flow on the relinquished portions of Route 111, including any traffic signal progression.

(c) (1) The commission may relinquish to the City of Palm Springs any portion, or the entirety, of Route 111 within its city limits, upon terms and conditions the commission finds to be in the best interests of the state, if the department and the city enter into an agreement providing for that relinquishment.

(2) A relinquishment under this subdivision shall become effective on the date following the county recorder’s recordation of the relinquishment resolution containing the commission’s approval of the terms and conditions of the relinquishment.

(3) On and after the effective date of the relinquishment, all of the following shall occur:

(A) Any portion of Route 111 relinquished pursuant to this subdivision shall cease to be a state highway.

(B) Any portion of Route 111 relinquished pursuant to this subdivision shall be ineligible for future adoption under Section 81.

(C) For any portion of Route 111 relinquished pursuant to this subdivision, the City of Palm Springs shall maintain signs within its city limits directing motorists to the continuation of Route 111.