Caulonia or Caulon was an ancient city on the shore of the Ionian Sea near Monasterace, Italy.

Caulonia is a comune (municipality) in the Province of Reggio Calabria in the Italian region Calabria, located about 60 kilometres (37 mi) southwest of Catanzaro and about 120 kilometres (75 mi) northeast of Reggio Calabria in the Stilaro Valley. Originally it was known as Castelvetere, but in 1862 the citizens decided to change the name of the town to that of the ancient city Caulonia. They believed that this city had been located on their territory, but it was eventually proved that ancient Caulonia was to be found near modern Monasterace, 16 kilometres (10 mi) to the northeast.