Grotta dei Colombi is a sea cave situated at the base of the Sant'Elia promontory near Villasimius. Accessible only by boat, the site is suited for intermediate snorkelers who can navigate the cave environment. The location is noted for its light play within the cave structure. Water temperatures in the area fluctuate throughout the year, ranging from 14C in March to 27C in August. As a marine site, it offers a distinct coastal experience for those exploring the waters of Sardegna.

Cala Fighera is a rugged cove situated beneath the Sella del Diavolo cliffs near Cagliari. The site features a rocky seabed and is accessible via a shore entry. It is suited for intermediate snorkellers who can navigate the wild atmosphere of this secluded location. Water temperatures fluctuate significantly throughout the year, ranging from 14C in March to 27C in August. Divers and snorkellers should be aware of potential hazards including entanglement, overhead environments, and sharp coral. On-site facilities include parking, showers, changing rooms, toilets, and a rinse station, with dive shops nearby offering air fills, equipment rental, boat charters, and guided tours.

Cala Bernat is a quiet cove in Villasimius, Italy, offering a peaceful environment for divers and snorkellers. The site features a mixed seabed of sand and rocks, with depths ranging from 1 to 8 metres and an average of 4 metres. Conditions are generally mild, with visibility varying between 5 and 15 metres. The site is suitable for beginners and accessible by both shore and boat. Divers should be aware of sea urchins present in the area. The habitat supports a variety of Mediterranean reef fish and invertebrates typical of the region. Typical dives last approximately 30 minutes.

Sant'Elia Lazzaretto Coves in Villasimius consist of a series of rocky inlets situated near the historic Lazzaretto building. This urban snorkeling site features interesting rock formations and is suitable for beginners. Access is via the shore, and the area experiences mild currents. Water temperatures fluctuate throughout the year, ranging from 14C in March to 27C in August. Divers and snorkellers should be aware of sharp coral present in the area. Facilities available at the site include parking and toilets.

Lt221 is a World War II tugboat wreck located off the coast of Villasimius. The vessel lies on its side and is split in half, resting at depths between 36 and 49 metres, with an average depth of 40 metres. Due to the significant depth and the nature of the structure, this site is reserved for advanced divers. Access is strictly by boat. Divers should be aware of moderate currents and potential hazards including the depth of the wreck and the risk of entanglement within the structure. Visibility at the site can reach up to 50 metres.

The Romagna is a Second World War tanker wreck located off the coast of Villasimius, Italy. Sunk by a floating mine, the vessel remains largely intact with the deck resting at 30 metres and the site reaching depths of 42 metres. Divers can explore the structure, including the propeller and rudder area, where the 1.8-metre long propeller blades are a notable construction feature. Due to the depth and strong currents, this site is strictly for advanced divers. Access is by boat only, as the wreck lies over 22 kilometres from the shore. The environment supports a variety of Mediterranean reef fish and invertebrates typical of this deep-water habitat.

Cala Regina is a rocky cove located 25km east of Cagliari, distinguished by a prominent Spanish watchtower overlooking the site. The seabed consists of rocky formations that reach depths between 2m and 15m, with an average depth of 7m. This shore-entry site is suitable for intermediate divers and offers visibility ranging from 10m to 25m. Currents are generally mild, though divers should be aware of sea urchins present in the area. With a 4/5 snorkel rating, the site is also accessible for surface exploration. Parking is available near the cove, and typical dives last approximately 60 minutes.

Mari Pintau in Villasimius is a coastal site featuring a smooth pebble entry that transitions into a sandy bottom. The site consists of a reef and an artificial reef, with a submerged anchor located on the right side. Depths range from 2 to 10 metres, with an average of 4 metres, making it suitable for beginners. Conditions include mild currents and potential surf. Facilities available at the site include parking, toilets, showers, and a cafe. Guided tours are also available for those visiting the area.