The city's name comes from Aleguerium, which is a mediaeval Latin word meaning "stagnation of algae" (Posidonia oceanica).

[4] Due to its strategic position on the Mediterranean Sea, Alghero had been developed into a fortified port town by 1102, built by the Genoese Doria family.

In the early 16th century, Alghero received papal recognition as a bishopric and the status of King's City (ciutat de l'Alguer) and developed economically.

In the north of the urban area, there is the Nurra plain; to the northwest, the karstic systems of Capo Caccia, Punta Giglio and Monte Doglia.

The most recent linguistic research showed that 24.1% of the people have Algherese Catalan as a mother tongue, which is habitually spoken by 18.5% and taught to the children by 8% of the population, whereas 88.2% have some understanding of the language.

Currently, there has been a revival of the arts in Algherese Catalan, with singers such as Franca Masu performing original compositions in the language.

[11] Following a rural exodus from the surrounding villages towards the city, much of the population speaks or has some proficiency in Sardinian, in addition to Italian and Catalan.

Historically, the spread of Catalan was limited to the city and part of the coast, as the surrounding countryside has always been populated by Sardinian-speaking people.

This Catalan population was the subject of an 1888 book by Eduardo Toda y Güell: Un poble català d'Itàlia: l'Alguer, which restarted the connection between Catalonia and Alghero.

Back from the Neolithic period from which many settlements remain, up to nowadays, in the last decades Alghero has become a touristic main point not only because of its coast and natural beauties but also because of a fairly well-preserved patrimony.

Several archeological sites out of the urban area: the Anghelu Ruju necropolis, the Santu Pedru hill, the Villa Romana of Santa Imbenia or even the Purissima.

Some features from the old walls were respected, but Ferdinand the Catholic, who wanted to grant more protection to the city, built the majority of them in the 16th century.

Indeed, this coral is one of the most important economic aspects of the territory, giving this stretch of the coast its name, the Riviera del Corallo.

In the 1930s the Swedish writer Amelie Posse Brazdova wrote a book entitled Sardinia Side Show, where she told the complete story of two years she spent "interned" in Alghero old town during World War I.