answer:They are to commemorate the route of Father Junipero Serra and his fellow Spanish missionaries and the (general) route that they followed when founding the missions of California, starting with the San DIego Mission in 1769. For a more complete history of the California Missions, go here The missions were one day’s walk from one another, the route being named El Camino Real (or the Highway of the King) for the King of Spain. Portions of the road are still referred to as El Camino. The bells that you see today, are, for the most part the original bells (symbolizes the bells at each mission) Most were stolen and a project was set up to replace them. They used to sell miniature replicas at the missions (I have one that was my dad’s), don’t know if they have revived that or not.