Ersa is a commune of the Haute-Corse department of France on the island of Corsica. Ersa is the northernmost commune of Corsica. It extends …Ersa is a commune of the Haute-Corse department of France on the island of Corsica. Ersa is the northernmost commune of Corsica. It extends from Centuri to the West, to Rogliano to the East. Ersa is covered with shrubs and arid summits. The coast, which is carved to the West by the Cape Grossu and the Punta of Corno of Becco, has beaches of sand and pebbles. The commune is watered by the streams Acqua Tignese and Granaghjulu on its undulating slopes of the Mount Maghjore.