Alghero is a town of about 44,000 inhabitants, next to the Mediterranean Sea. Part of its population descends from Catalan conquerors from the end of the Middle Ages, when Sardinia was part of the Crown of Aragon. That is why the Catalan language is co-official in the city, unique in Italy, taking the name of alguerès dialect. The name Alghero comes from the medieval Latin Aleguerium, meaning stagnation of algae.