Les Arches is a reef site located 1500 metres off the coast of Saint-Malo, France. This site is suited for intermediate divers and requires boat access. The topography is consistent, with an average depth of 11 metres. Divers should be prepared for moderate currents and surge conditions, and remain vigilant for boat traffic in the area. Typical dives at this location last approximately 45 minutes. Water temperatures fluctuate throughout the year, ranging from 11C in the spring to 16C in August.

Carrec An Ti, located near Saint-Malo, France, is a marine site suitable for beginners. The site maintains a consistent depth of approximately 10 metres. Water temperatures fluctuate between 11C and 16C throughout the year, requiring appropriate thermal protection to mitigate the risk of hypothermia. While specific observations at this exact location are limited, species recorded around this area include various crustaceans such as crabs, squat lobsters, and spiny spider crabs, as well as wrasses, conger eels, and sea slugs. Soft corals and brittle stars are also present in the surrounding waters. The site is accessible for both diving and snorkelling activities.

Le Diben is a shore-entry reef dive located in the Baie de Morlaix. The site features a reef structure ranging from 10 to 20 metres in depth, making it suitable for beginner divers. Visibility typically fluctuates between 5 and 15 metres. Divers should expect moderate currents and plan entries and exits according to tidal movements. Water temperatures remain cool, between 11 and 14 degrees Celsius, necessitating appropriate thermal protection. Due to the presence of vessel traffic, the use of a surface marker buoy is essential at all times to ensure visibility. On-site facilities include showers and toilets for post-dive use.

Pierre Noire is a reef site located off the coast of Saint-Malo, France. This site is suited for intermediate divers and requires boat access. The topography consists of a reef structure with an average depth of 10 metres. Divers should be aware of moderate currents and potential hazards including entanglement and sharp surfaces. Water temperatures at this location range from 11C in the winter months to 16C in August. Night diving is permitted at this site. Due to the nature of the environment, divers should maintain good buoyancy control to navigate the reef safely.

Fourche Noire is a reef and wall dive site located off the coast of Saint-Malo, France. The site features a consistent depth of approximately 9 metres, making it suitable for beginner divers. Access to the site is by boat only. Divers should be prepared for moderate currents and variable visibility ranging from 3 to 10 metres. Water temperatures fluctuate throughout the year, reaching a high of 17C in August and a low of 11C during the winter months. Hazards at this location include sea urchins, surf, and strong currents. Typical dives at this site last around 45 minutes.

La Noire in Saint-Malo, France, is a marine site featuring a combination of reef and seagrass habitats. Divers can expect a consistent depth of 10 metres. Access to the water is via a shore entry. Conditions at this location are generally mild, though divers should remain aware of boat traffic in the area. Water temperatures fluctuate throughout the year, ranging from 11C in the winter months to 16C in August. This site is suitable for beginner divers looking to explore local coastal habitats.

La Base à Dom is a marine dive site located in Saint-Malo, France. The site features a consistent depth of approximately 10 metres. Water temperatures in this area fluctuate throughout the year, ranging from 11C in the winter months to 16C during August. Given the depth and environmental conditions, this site is suitable for divers with appropriate cold-water experience. Access to the site is typically managed via boat from the local area. As a marine environment, the topography is subject to the tidal conditions characteristic of the Brittany and Normandy region.

Île Noire is a dark, rocky reef located near the Château du Taureau in the Baie de Morlaix. This site offers depths ranging from 0 to 21 metres and requires boat access. Divers and snorkellers should be prepared for moderate currents and water temperatures between 11C and 14C, which remain cool throughout the year. Species recorded around this area include crabs, wrasses, squat lobsters, conger eels, flatworms, common lobsters, catsharks, spiny spider crabs, shrimp, sea stars, sea hares, soft corals, abalone, and gray seals. Due to the conditions and depth, this site is suited for advanced divers.