Capo Galera is a rocky headland near Alghero featuring a series of underwater arches and small caves. The site is suitable for intermediate divers, with depths ranging from 5 to 15 metres and an average depth of 10 metres. Divers and snorkellers can expect visibility between 15 and 30 metres. Water temperatures fluctuate seasonally from 14C to 25C, with a thermocline typically occurring at 12 metres where temperatures drop to 15C. Access is available via both shore and boat. Facilities at the location include parking, toilets, showers, changing rooms, a rinse station, air fills, equipment rental, a cafe, a dive shop, boat charter, guided tours, and gear storage.

Cala Bramassa is a reef and cave site located within the Porto Conte Regional Park near Alghero. Situated 1500 metres from the shore, this site features a rocky seabed with depths ranging from 2 to 18 metres, averaging 12 metres. The bay's shape provides protection from most winds, resulting in visibility between 5 and 20 metres. Water temperatures fluctuate between 14C and 26C, with the bay being slightly warmer than neighbouring coves. Access is possible by both shore and boat, though the site is best suited for intermediate snorkellers. Hazards include entanglement, overhead environments within the caves, and sharp coral. Parking is available for visitors.

Scoglio d'Inferno is a pinnacle reef near Alghero that breaks the surface. This site features two arches and reaches a maximum depth of 19 metres, with an average depth of 13 metres. It is suitable for beginners and offers mild currents. Divers frequently encounter white seabream, wrasses, and striped red mullet. Less common sightings include Turkish wrasse, bream, two-banded seabream, and salema porgy. Snails are also commonly observed on the reef. Access is by boat only, and divers should remain aware of potential boat traffic in the area.

Cala del Bollo is a wild cove located near the Torre del Bollo in Alghero. The site features a rugged underwater environment characterised by a combination of rocky reefs and Posidonia seagrass meadows. Snorkellers can expect depths ranging from 5 to 7 metres, with an average depth of 6 metres. Visibility at this site varies between 10 and 25 metres, and currents are generally mild. Access to the water is possible from both the shore and by boat. Facilities available at the location include parking, toilets, showers, and a cafe. The site is suitable for intermediate snorkellers, with a typical session lasting approximately 60 minutes.

Grotta di Nettuno is a complex site near Alghero featuring a combination of cave passages, vertical walls, and drop-offs. Divers typically explore depths between 20 and 30 metres, with visibility ranging from 10 to 30 metres. The site requires advanced open water and cave diving certifications due to the overhead environment within the cave system. Access is exclusively by boat, located 5000 metres from the shore. While currents are generally mild, they can strengthen, and divers must remain vigilant for boat traffic when surfacing. The water temperature fluctuates between 14 and 22C, though the interior of the cave remains a consistent 18 to 20C.

The Tunnel in Alghero, Italy, is a versatile dive site featuring a combination of cave, cavern, reef, and wall topography. Accessible by boat, the site offers an average depth of 12 metres with a maximum depth of 18 metres. Divers can explore the varied underwater structures, which are noted for their distinct sunlight effects. Conditions are generally mild, making this an accessible location for beginners. Due to the presence of boat traffic in the area, divers should remain vigilant during ascents and descents. The site is suitable for various experience levels, allowing for different routes through the tunnel and surrounding reef formations.

The Colonnade is a versatile dive site near Alghero, Italy, featuring a combination of wall, reef, and cavern topography. Divers navigate through a series of windows, swim-throughs, and arches that create distinct light effects. The site is accessible only by boat, located 1000 metres from the shore. With depths ranging from 5 to 18 metres and an average of 12 metres, it is suitable for beginners. Visibility typically spans 15 to 30 metres. A thermocline is present at approximately 12 metres, where temperatures drop to 15°C. Divers should be aware of sharp coral present at the site. Night diving is available, and typical dive times are around 50 minutes.

Bramassa is a diverse marine site located in Alghero, Italy, offering a variety of underwater topography including reefs, walls, caves, and canyons. The site is accessible by boat and is suitable for beginners, with depths ranging from 8 to 15 metres and an average depth of 12 metres. Divers can explore tunnels and windows that create distinct light effects, particularly during the afternoon. Conditions are generally mild, though divers should remain aware of boat traffic in the area. The site provides a varied environment for those interested in geological formations and coastal Mediterranean diving.