This is the 1958 "Adopted Alignment" that Caltrans advanced to connect Pacifica with Half Moon Bay, and intended to connect with the then-existing SR1 freeway in Pacifica. That it began at the Pacifica city limits placed it almost entirely inside the unincorporated area of the coast (not that it mattered). I have another map that depicts the Martini Creek Alignment; it's just a shortened version of the Adopted Alignment. By the way, Judge Sweigart told Caltrans to forget the Adopted Alignment after it was sued in 1971. There are a lot of "wrinkles" to the ongoing attempts by the political power structure to build out the San Mateo County coast, i.e., urbanize it. The oversimplifications advanced by some of the recent commenters on Riptide don't change the facts.