Walking to Castelsardo while avoiding the main road.

I was visiting Lu Bagno and wanted to go to Castelsardo without walking too much on the main road, as there is a small curvy stretch of main road without any real footpath. I did actually walk the main road on my way back, but this involves climbing over a road barrier and can't or shouldn't be done with kids. The route through the back land is a nice albeit longer alternative and will take you through beautiful countryside and lost places, also past the well stocked Eurospin Supermarket and the marina/port of Castelsardo. Once in Castelsardo, you get some amazing views going up to the old Castello, which also features a museum.