Close to beach castle for vacation rentals in Corsica (Upper)

Upper Corsica represents the entire northeastern part of the island. It is bordered by the Tyrrhenian Sea to the east and the Mediterranean to the west. The number of second homes in Corsica is very high, much higher than in the rest of France. But who wouldn't like to live there after discovering its magnificent sea and mountain landscapes, its preserved traditions, its pleasant climate and its flagship cities (Bastia, Biguglia, Calvi, L'île Rousse or Saint-Florent)?