California State Route 203 is an approximately nine-mile State Highway located near Mammoth Lakes in the Sierra Nevada Mountains of Mono County. California State Route 203 as presently configured begins at US Route 395, passes through Mammoth Lakes and terminates at the Madera County line at Minaret Summit. What is now California State Route 203 was added to the State Highway System in 1933 as Legislative Route Number 112. The original Mammoth Lakes State Highway ended at Lake Mary near the site of Old Mammoth and was renumbered to California State Route 203 in 1964. The modern alignment of the highway to Minaret Summit was adopted during 1967. The corridor of Minaret Summit and Mammoth Pass have been subject to numerous proposed Trans-Sierra Highways. The first corridor was proposed over Mammoth Pass following a Southern Pacific Railroad survey in 1901. In 1931 a corridor between the Minarets Wilderness and High Sierra Peaks Wilderness wa...
Because every road has a story.