The mediaeval fortified town of Terzorio is situated in the hinterland behind Santo Stefano al Mare in a position overlooking the Rio Santa Caterina valley. Included in the donation made by Adelaide di Susa to the Benedictines in 1049, Terzorio became a part of the feudal estate of the Ventimiglia nobility and part of the principality of Villaregia. From 1228 it belonged to Bonifacio di Lingueglia, but near the end of the same century it became a "villa" with its own statutes (1277). In 1353 it was placed under the jurisdiction of the Republic of Genoa. It was probably because of Saracen incursions in the sixteenth century that the watchtower was built. The upper part of the town, with its archivaults and old alleyways, is mediaeval.
The parish church of the Natività di San Giovanni Battista (1729) is well worth a visit. The local silver mines were opened in 1850. They were worked in the past by a Belgian company and can now be visited through the Italian Alpine Club. The surrounding countryside is characterised by cultivated lavender fields lying next to the "stradina" "yellow" and "Imperia" varieties of marguerites and, of course, by traditional olive trees.
Terzorio has for some time hosted national motorcycle, jeep and endurance competitions. The typical speciality here consists of puff pastry filled with vegetables and fried.
