St. Nicholas Islet in Santorini offers a reef environment accessible via a concrete platform entry located past the Oia seafood tavernas. The site features a deep channel leading to the islet, with depths ranging from 3 to 30 metres and an average of 15 metres. Divers and snorkellers can expect visibility between 15 and 30 metres. Conditions include mild currents and water temperatures fluctuating between 17C and 24C throughout the year. Due to the depth and potential for boat traffic, this site is suited for advanced divers. Parking is available near the entry point.

Ammoudi Reef Wreck in Santorini offers a diverse underwater landscape featuring a reef, a wall, and a wreck. The site is suitable for intermediate divers, with depths ranging from 5 to 30 metres and an average depth of 17 metres. Visibility typically spans 15 to 30 metres, allowing for clear observation of the varied topography. Currents are generally mild, though divers should remain aware of boat traffic in the area. Access is possible via both shore and boat, with parking and cafe facilities available nearby. Dives typically last around 45 minutes, with water temperatures fluctuating between 17C and 24C throughout the year.

Thirasia 1 is a wall and reef site located off Santorini, Greece, accessible only by boat. The topography features a reef that transitions into a wall, dropping from 18 metres to depths of 50 metres. With visibility consistently around 30 metres and mild currents, the site is manageable for divers. Due to the significant depth of the wall, divers must monitor their gauges closely and agree on a turnaround depth before entering the water. The site is suitable for beginners who remain on the shallower sections of the reef to extend their bottom time. Typical dives last 45 minutes, with guided tours and boat charters available for access.

Thirasia 2 is a reef and wall dive located off the island of Thirasia within the Santorini caldera. The site features depths ranging from 10 to 15 metres, with an average depth of 12 metres. Visibility varies between 10 and 30 metres, and the site is suitable for beginners. Access is by boat only, and divers should remain close to their guide due to boat traffic. Divers must maintain good buoyancy to avoid contact with the sharp reef and wall structures. Typical dives last approximately 45 minutes, with conditions varying depending on the time of day.

Riva Santo in Santorini, Greece, offers a combination of reef and wall topography suitable for various skill levels. The site features a depth range of 5 to 45 metres, with an average depth of 15 metres, allowing beginners to explore the shallower reef sections. Divers can access the site via both shore and boat entries. Visibility typically ranges between 10 and 30 metres. A moderate current is common, so divers should monitor conditions and consider timing dives around slack water. Facilities at the shore entry point are limited, and it is recommended to consult local dive operators regarding daily current patterns and site access.

Korfos is a reef and cave system located in Santorini, Greece, offering intermediate divers a varied underwater environment. The site spans depths from 5 to 30 metres, with an average depth of 20 metres. Visibility is generally good, ranging between 20 and 30 metres. Access is by boat only, and divers should maintain controlled buoyancy to avoid contact with sharp rocks and coral present throughout the cave sections. A torch is recommended to explore the cave features effectively. Species recorded around this area include Mediterranean moray, Turkish wrasse, white seabream, and various species of nudibranchs such as the Mediterranean violet aeolid.

Skaros Wall is a reef and wall dive site located in Santorini, Greece. The site maintains a consistent depth of 10 metres, making it well-suited for beginner divers. Divers access the site exclusively by boat. Conditions are stable with no current and visibility reaching 30 metres, providing a clear environment for buoyancy practice and reef observation. Water temperatures range from 17C in the winter and spring months to 25C during the peak of summer. The site offers a straightforward underwater experience within the Aegean Sea, allowing divers to explore the reef structure at a relaxed pace.

Afalatosi is a varied underwater site in Santorini featuring a combination of reef, wall, and cave topography. Reached exclusively by boat, the site ranges from 15 to 30 metres in depth, with an average of 17 metres. Visibility typically spans 15 to 30 metres, assisting navigation along the walls and cave entrances. A mild current is common, though divers should be aware that surge and swell can develop, particularly within the cave sections. Due to the depth range and potential for surge, this site is suited for intermediate divers. Divers should monitor conditions closely and coordinate with local operators, as sea states around Santorini can shift with little warning.