Plage des Kaolins on Île de Groix offers a reef environment accessible from the shore. The site features rocky sections at either end of a long sandy stretch, providing varied topography for snorkelers. Depths range from 1 to 15 metres, with an average depth of 5 metres. Conditions include moderate currents and potential surf, requiring intermediate skill levels. Visibility typically spans 5 to 10 metres. Water temperatures fluctuate between 10C and 18C, making cold water shock a consideration for those entering the water. Facilities at the site include parking, toilets, and showers.

The U 171 wreck is a deep-water dive site located 2000 metres off the coast of Île de Groix, France. This site is reserved for advanced divers due to its depth, which ranges from 18 to 40 metres with an average of 38 metres. Access is strictly by boat. Divers should be aware of the risk of entanglement when exploring the wreck structure. Visibility at the site fluctuates between 5 and 25 metres, and water temperatures remain cool, ranging from 11 to 15 degrees Celsius throughout the year. Typical bottom time for this dive is approximately 40 minutes.

Port Blanc at Kerroc'h is a rocky reef site located on the Île de Groix. This shore entry location features a rugged topography characterised by deep crevices and kelp forests accessible with a short swim. The site is suitable for beginners and offers mild currents. Water temperatures fluctuate between 10C and 18C throughout the year, making wetsuits advisable outside of the summer months. Facilities available at the site include parking, toilets, and showers. Divers and snorkellers should be aware of potential hazards including jellyfish and sea urchins in the area.

Plage du Pérello on the Île de Groix is a sheltered cove featuring a sandy bottom framed by rocky ridges. This site is suitable for beginners, offering a shallow snorkeling experience with depths ranging from 1 to 10 metres and an average depth of 5 metres. Access is via the shore, and the area experiences mild currents. Visibility typically fluctuates between 5 and 15 metres. Visitors should be aware of potential surf conditions. On-site facilities include parking, toilets, showers, and a rinse station for equipment.

Pointe de Pen Men is a reef and wall site located at the western tip of Île de Groix. The topography features a wall dropping to a maximum depth of 22 metres, with an average depth of 15 metres. This site is accessible only by boat due to strong surf and shore breaks at the coast. Divers can expect mild currents and visibility ranging from 5 to 10 metres. Water temperatures fluctuate between 11 and 16 degrees Celsius throughout the year, necessitating appropriate thermal protection. The site is suitable for beginners, though divers should remain vigilant regarding potential entanglement hazards within the reef structures.

Anse du Stole on the Île de Groix is a family-friendly beach that offers accessible snorkelling from the shore. At low tide, the site transforms into a series of shallow rock pools and edges, providing a calm environment suitable for beginners. Water temperatures at this location vary throughout the year, ranging from 10C in February to 18C during the summer months between July and September. The site is well-suited for those looking for a relaxed snorkelling experience in a sheltered coastal setting.

Poullziorek, also known as Tahiti Beach, is a reef site on the Île de Groix featuring white sand and a shallow depth range of 2 to 10 metres. With an average depth of 5 metres, it is well-suited for snorkeling, which is highly rated here. Access is via the shore, though divers and snorkellers should be aware of moderate currents, surf, and rip currents. The water is notably cold, ranging from 10C to 17C throughout the year. Species recorded around this area include wrasses, conger eels, various crabs, sea stars, and European common cuttlefish. Parking is available near the site.

Kelhuit is a reef dive located 800 metres off the coast of Île de Groix, France. This site is well suited for beginner divers, offering a shallow profile that ranges from 1 to 15 metres with an average depth of 8 metres. Access is by boat only. Divers can expect mild currents and visibility typically between 5 and 10 metres. The site is suitable for night diving, allowing for a different perspective of the reef structure. Water temperatures fluctuate between 10 and 17 degrees Celsius throughout the year, necessitating appropriate thermal protection such as a 7mm wetsuit during colder months. Typical dive duration is approximately 40 minutes.