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.

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 Canyon in Alghero is a deep wall and canyon formation suited for advanced divers. The dive features a large archway at approximately 38 metres, leading into a canyon lined with gorgonian fans. Divers typically descend to an average depth of 30 metres, with the site reaching a maximum of 40 metres. Access is by boat only, and conditions involve variable currents with visibility ranging from 15 to 30 metres. Water temperatures fluctuate between 14C and 21C throughout the year. Due to the depth of the topography, this site is strictly for experienced divers holding a deep diver certification.

Isola Foradada is a limestone rock formation located 5000 metres from the shore near Alghero. The site features vertical walls and a sea cave, with depths ranging from 0 to 15 metres and an average of 14 metres. Access is by boat only. Conditions vary, with visibility between 5 and 25 metres and mild currents. The site is suitable for beginners and offers a 5/5 rating for snorkelling. Night diving is available. Species recorded around this area include wrasses, Mediterranean moray, common octopus, great barracuda, conger eel, various nudibranchs, and crustaceans. Be aware of boat traffic in the area.

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.

Grotta di Nereo, located behind the Capocaccia promontory near Alghero, is a complex cave and wall system extending 400 metres. Divers can access the site at depths of 15, 18, and 30 metres, with an average depth of 15 metres and a maximum of 35 metres. The site features large cavernous environments suitable for intermediate divers. Access is strictly by boat, located 200 metres from the shore. Conditions include mild currents and visibility ranging from 10 to 35 metres. Water temperatures fluctuate between 14C and 21C throughout the year. Species recorded around this area include wrasses, Mediterranean morays, common octopus, and various nudibranchs.

Punta Timone in Alghero, Italy, offers a diverse underwater landscape featuring a reef, wall, and cave system. Divers typically explore the wall to reach a natural window that leads to the opposite side of Foradada Island. The site is suitable for beginners, with depths ranging from 5 to 18 metres and an average depth of 14 metres. Conditions are generally mild, with visibility between 15 and 30 metres. A thermocline is present, and water temperatures fluctuate between 14C and 24C throughout the year. Boat access is required to reach the site, and divers should remain aware of boat traffic in the area. Guided tours, equipment rental, and air fills are available.

Isola Foradada Dolmen is a diverse site in Alghero, Italy, featuring a combination of reef, wall, and cave topography. Divers can explore two large boulders that rise near the surface before navigating a short tunnel that transitions from 14 metres to 5 metres depth. The site is accessible by boat and is suitable for intermediate divers, with depths ranging from 5 to 30 metres and an average depth of 14 metres. Conditions include mild currents and visibility reaching up to 20 metres. Hazards to note include boat traffic, sharp coral, and surge. Night diving is permitted at this location, with typical dive times lasting approximately 50 minutes.