Alghero is a city of about 45,000 inhabitants in the Italian insular province of Sassari in northwestern Sardinia, next to the Mediterranean Sea. The city's name comes from Aleguerium, which is a mediaeval Latin word meaning "stagnation of algae".

Algherese or Alguerese is the variant of Catalan spoken in the city of Alghero, in the northwest of Sardinia, Italy.