From the plaque:
This plaque was placed on
the 250th anniversary of the birth of California's apostle,
Padre Junípero Serra, OFM, to mark northern terminus of El Camino Real
as Padre Serra knew it and helped blaze it. 1731 - November 24 - 1963
Plaque placed by the California State Park Commission in cooperation with the Committee for El Camino Real November 21, 1963.