California Code, Public Resources Code - PRC § 5025.11

The department shall, with the advice of the Historical Landmarks Advisory Committee, or, as to certifications on or after January 1, 1975, with the advice of the commission, certify the route followed by Colonel John Charles Fremont and party from the Nevada state line through Mono, Inyo, Alpine, Amador, and El Dorado Counties to Sutter's Fort in Sacramento County in the winter of 1843, and the Donner Party Trail, from the Nevada state line to the junction of Verdi Canyon to Alder Creek Camp of the Donner Party, thence to the Donner Monument at Donner Memorial State Park. The department may certify and mark, with the advice of the commission, other historic routes of travel within the state.