Alghero was designated as a diocesan seat in 1503 but construction work on the cathedral did not begin until 1567. It was inaugurated in 1593 but was not finished. After several restorations it was consecrated in 1730.
The church was originally in Catalan-Gothic style, as can be seen in the five chapels and ambulatory of the presbytery, which also includes the octagonal base of the bell tower. The nave and the two aisles are however in Late Renaissance style. The main altar was designed by the Genovese artist Giuseppe Massetti (1727): the sculpture shows Mary the Immaculate flanked by angels. He also designed the ambulatory and the pulpit. In 1862 a Neo-Classical narthex was added to the façade, which dramatically changed its appearance.
The first chapel on the right side is dedicated to the Blessed Sacrament. Its imposing, marble altar was inaugurated in 1824. It is located inside a circular temple, reminding the Temple of Vesta in Rome.
The cathedral is the burial site of the Italian-born Duke of Montferrat (1762-1799) and his brother Count of Asti (1766-1802) who died on the island having caught malaria. The marble mausoleum was sculpted by Felice Festa in the early 19th century.
References:La Hougue Bie is a Neolithic ritual site which was in use around 3500 BC. Hougue is a Jèrriais/Norman language word meaning a \'mound\' and comes from the Old Norse word haugr. The site consists of 18.6m long passage chamber covered by a 12.2m high mound. The site was first excavated in 1925 by the Société Jersiaise. Fragments of twenty vase supports were found along with the scattered remains of at least eight individuals. Gravegoods, mostly pottery, were also present. At some time in the past, the site had evidently been entered and ransacked.
In Western Europe, it is one of the largest and best preserved passage graves and the most impressive and best preserved monument of Armorican Passage Grave group. Although they are termed \'passage graves\', they were ceremonial sites, whose function was more similar to churches or cathedrals, where burials were incidental.