Castelsardo Cathedral is dedicated to Saint Anthony the Great. It became the seat of the bishop of Ampurias in 1503. In 1839 the diocese of Ampurias was merged into that of Tempio, and the episcopal seat moved to Tempio Cathedral, when that of Castelsardo became a co-cathedral, as it remains in the present diocese of Tempio-Ampurias.
The current building dates from the reconstruction begun in 1597 that lasted until the 18th century. The cathedral is a mixture of Catalan Gothic and Renaissance elements, and overlooks the sea directly. The interior is on the Latin cross plan, with a single nave with barrel vaults, side chapels and transept. The crossing has a cross vault on four pilasters with sculpted capitals.
The church has a tall bell-tower, topped by a small dome decorated with majolica.
The presbytery is raised, and has a marble balustrade. The apse, with a cross vault decorated with stars, houses the marble high altar of 1810, characterized by the church's main attraction, the Enthroned Madonna and Child, a painting of the 15th century, attributed to the Master of Castelsardo. Also by the latter artist is a St. Michael the Archangel, displayed in the crypt, now home to the diocesan museum.References:
Monte d"Accoddi is a Neolithic archaeological site in northern Sardinia, located in the territory of Sassari. The site consists of a massive raised stone platform thought to have been an altar. It was constructed by the Ozieri culture or earlier, with the oldest parts dated to around 4,000–3,650 BC.
The site was discovered in 1954 in a field owned by the Segni family. No chambers or entrances to the mound have been found, leading to the presumption it was an altar, a temple or a step pyramid. It may have also served an observational function, as its square plan is coordinated with the cardinal points of the compass.
The initial Ozieri structure was abandoned or destroyed around 3000 BC, with traces of fire found in the archeological evidence. Around 2800 BC the remains of the original structure were completely covered with a layered mixture of earth and stone, and large blocks of limestone were then applied to establish a second platform, truncated by a step pyramid (36 m × 29 m, about 10 m in height), accessible by means of a second ramp, 42 m long, built over the older one. This second temple resembles contemporary Mesopotamian ziggurats, and is attributed to the Abealzu-Filigosa culture.
Archeological excavations from the chalcolithic Abealzu-Filigosa layers indicate the Monte d"Accoddi was used for animal sacrifice, with the remains of sheep, cattle, and swine recovered in near equal proportions. It is among the earliest known sacrificial sites in Western Europe.
The site appears to have been abandoned again around 1800 BC, at the onset of the Nuragic age.
The monument was partially reconstructed during the 1980s. It is open to the public and accessible by the old route of SS131 highway, near the hamlet of Ottava. It is 14,9 km from Sassari and 45 km from Alghero. There is no public transportation to the site. The opening times vary throughout the year.