El Gruñon is a reef site located off Mataro, Spain, featuring depths between 14 and 23 metres. Accessible only by boat, the site offers visibility ranging from 5 to 25 metres. The topography consists of rocky reef structures and meadows of Posidonia oceanica seagrass. Conditions are generally manageable for beginner divers due to mild currents. Divers should exercise caution regarding buoyancy control, as the reef contains sharp and uneven rock formations. Water temperatures fluctuate significantly throughout the year, ranging from 13C in February to 23C in August and September, necessitating appropriate thermal protection for the season.

Canons is a varied underwater site featuring a reef, wall, and canyon system located 1000 metres off the coast of Mataro. The topography drops from 8 to 40 metres, with an average depth of 20 metres. Divers encounter moderate currents that can strengthen within the canyon sections, requiring solid buoyancy control. Visibility typically ranges between 15 and 25 metres. The site is suitable for intermediate divers and supports night diving. Water temperatures fluctuate between 13 and 19 degrees Celsius throughout the year. Due to the significant depth and potential for strong currents, divers should monitor air supply and decompression limits closely while avoiding sharp coral and rocks.

El Negre 15-22 in Mataro, Spain, offers a varied underwater landscape featuring a reef, wall, and drop-off. The site ranges from 4 metres to 27 metres in depth, with an average depth of 15 metres. Suitable for beginners, the site experiences mild currents and visibility between 5 and 30 metres. Access is by boat only, and guided tours are available through the local dive shop to help navigate the wall and crevices. Water temperatures fluctuate throughout the year, ranging from 13C in February to 23C in August and September. Divers should plan their thermal protection according to the seasonal temperature variations.

El Negre Petit is a reef dive located off the coast of Mataro, Spain. The site features a reef structure that descends from 8 metres to a maximum depth of 25 metres, with an average depth of 18 metres. This site is suitable for beginners due to the mild currents and the ability to choose a depth that matches individual comfort levels. Visibility is typically around 9 metres. Boat access is required to reach the site, and local facilities provide air fills, boat charters, and guided tours. Divers should note that water temperatures fluctuate between 13 and 23 degrees Celsius throughout the year.

El Triangle is a reef site located 1000 metres offshore from Mataro, Spain. Accessible only by boat, the site features a rocky reef structure ranging from 8 to 20 metres in depth, with an average depth of 12 metres. Divers can expect mild currents and visibility typically between 10 and 25 metres. The site is suitable for beginner divers, though careful buoyancy control is required to avoid contact with sharp rocks and sea urchins found within the reef crevices. Water temperatures fluctuate seasonally from 13C in winter to 24C in late summer, necessitating appropriate thermal protection for the time of year.

Negre is a marine site in Mataro, Spain, featuring a combination of a shallow reef and a wall that descends to 25 metres. With an average depth of 13 metres and mild currents, the site is suitable for beginners. Visibility ranges from 10 to 30 metres, allowing for clear observation of the white gorgonians and rock fauna. Species recorded around this area include Mediterranean moray, common octopus, great barracuda, marbled electric ray, wrasses, Turkish wrasse, flatworms, Mediterranean violet aeolid, cow snail, scorpionfish, Cratena slug, flamingo tongue, torpedo ray, and sea stars. Boat access is required, and local facilities provide air fills and charter services.

El Templo is a deep reef site located off the coast of Mataro, Spain. The reef structure extends from 25 to 35 metres, requiring advanced diving skills and careful gas management. Divers should maintain solid buoyancy control while navigating the rocky substrate. Visibility varies significantly, ranging from 6 to 21 metres depending on conditions. Water temperatures fluctuate between 13 and 20 degrees Celsius throughout the year, making appropriate thermal protection essential. Access to this site is strictly by boat, and divers must monitor bottom time and decompression requirements closely due to the significant depth. The site is best suited for experienced divers comfortable with deep-water environments.

Balis 22 is a reef site located off Mataro, Spain, accessible only by boat. The reef structure extends from the surface to a maximum depth of 21 metres, making it suitable for beginner divers. Conditions are generally mild, with currents described as mild and visibility ranging between 15 and 30 metres. Water temperatures fluctuate significantly throughout the year, from 13C in winter to 24C in late summer, requiring appropriate thermal protection. Divers can explore the reef surface and its various crevices. Local facilities include a dive shop and equipment rental services, allowing visitors to source gear on-site.