https://www.siliconvalley.com/2023/01/17/slip-sliding-away-the-name-of-the-game-on-scenic-highway-1/

BIG SUR — The engineers and laborers who constructed California State Route 1 from Carmel to San Luis Obispo County beginning in the 1920s knew the road was fraught with peril. But they did it anyway. Coastal communities in the area needed better access to health care and other resources.

Engineers and prisoners alike risked life and limb as they built the two-lane highway into the majestic coastal cliffs of the Santa Lucia mountains. The 18-year project eventually connected San Luis Obispo to Carmel via the seaside, where the geology makes the road inherently susceptible to landslides. The 1937 grand opening even included a symbolic blasting of a boulder, which the governor cleared from the road with a bulldozer. It was the first of many to come.