Grotta delle Cipree is a cave and reef site located off the coast of Ustica. Divers access this location by boat, with depths ranging between 18 and 23 metres. The site features an overhead environment that requires strict buoyancy control and adherence to cavern certification standards. Visibility is consistently high at 30 metres, and the area experiences mild currents. A halocline within the cave maintains a constant temperature, though ambient water temperatures vary from 15 to 23 degrees Celsius throughout the year. Guided tours are strongly recommended for first-time visitors to safely navigate the cave layout and swim-throughs.

Grotta della Pastizza is a versatile site located 500 metres off the coast of Ustica, Italy. The topography consists of a wall and a cave system featuring two internal air pockets. The cave interior houses a statue of S. Bartolo, the patron saint of the island. With an average depth of 10 metres and a range of 8 to 12 metres, the site is suitable for beginners and offers a 4/5 rating for snorkelling. Access is by boat, and the site experiences mild currents with visibility ranging from 10 to 30 metres. Night diving is permitted, and guided tours are available through local dive shops.

Sutta zia Lisa in Ustica, Italy, offers a diverse underwater landscape featuring a steep vertical wall, caves, canyons, and pinnacles. The site ranges in depth from 3 to 30 metres, with an average depth of 20 metres. Divers can explore fissures and boulder formations throughout the area. Access to this site is by boat only. Conditions are generally stable with mild currents and visibility ranging between 15 and 40 metres. Water temperatures fluctuate seasonally, reaching a high of 22C in October and a low of 15C during the winter months. This site is suitable for intermediate divers, with typical dive times lasting approximately 50 minutes.

Grotta Totò is a technical cave dive located off the coast of Ustica, Italy. The site features an overhead environment at depths ranging from 10 to 18 metres, with an average depth of 13 metres. Access is exclusively by boat. Divers must maintain strict buoyancy control and carry redundant lighting, as the cave interior presents limited light and no direct ascent options. Conditions are generally manageable with mild currents at the entrance. Water temperatures fluctuate between 15C and 25C throughout the year. Proper gas management and adherence to cave diving certification limits are essential for this dive.

Grotta delle Stalattiti in Ustica is an expert-level cave dive featuring significant geological formations. Divers access the site by boat to explore chambers containing stalactites and stalagmites, including a large formation known as The Palm Tree. The site involves an overhead environment where the entrance may be lost from view within the tunnel system. Depths range from 14 to 20 metres, with an average of 12 metres. Conditions include mild currents and water temperatures varying between 15C and 25C. Marine life recorded at the site includes bream, wrasses, European parrotfish, and various invertebrates such as the Mediterranean violet aeolid, Cratena slug, and purple sea star.

Secchitello is a prominent pinnacle and reef system located 1609 metres off the coast of Ustica, Italy. The site features large pinnacles rising from a depth of 50 metres to approximately 24 metres. Divers encounter a variety of marine life including Great Barracuda, European Parrotfish, Mediterranean Violet Aeolid, Cow Snail, and various wrasses. Other species recorded at the site include Mediterranean Cardinalfish, Bream, Painted Comber, Hermit Crab, Violescent Sea-whip, Purple Sea Star, Two-banded Seabream, Marine Goldfish, and hard coral. Due to strong currents and depths reaching 50 metres, this site is strictly for advanced divers. Boat access is required for this 30-minute dive, which offers visibility of 30 metres.

Grotta Azzurra in Ustica is a marine cave and reef site accessible by boat, located 500 metres from the shore. The site features a large sea cave where sunlight creates a distinct blue glow within the water. Snorkellers can explore the interior of the cave and the surrounding volcanic walls. Conditions are generally suitable for beginners, with mild currents and depths ranging from 5 to 25 metres, averaging 10 metres. Visibility varies between 6 and 25 metres. Water temperatures fluctuate throughout the year, ranging from 15C in winter to 28C in August. Hazards at this site include sea urchins and sharp coral.

Sutta zà Lisa is a boat-access site off Ustica, Italy, featuring a diverse underwater landscape of reef, wall, cave, and canyon formations. Divers typically explore between 10 and 30 metres, with an average depth of 20 metres. The site is suited to intermediate divers, offering a varied topography that remains manageable due to mild currents. Visibility can be variable, so local checks are recommended before diving. Water temperatures fluctuate between 15C and 22C throughout the year, requiring careful selection of exposure protection. Species recorded around this area include various wrasses, groupers, Mediterranean moray, common octopus, and several species of nudibranchs.