Southern Coast and Archipelago is Finland's primary diving region, built almost entirely around wreck diving. The Helsinki sub-area holds the greatest concentration of sites, with reefs and wrecks spread across boat-accessible waters. Porkkala offers deep, demanding wrecks requiring cold-water experience, while the Turku Archipelago adds shallower options suited to a range of skill levels. Water is cold year-round, reaching its warmest in late summer. Visibility is variable. Dogfish, Righteye Flounder, and Sea Anemone are consistently observed, with occasional Herring schools and rare encounters with Gray Seal and Conger Eel.
3 areas
11Cold-water wreck and reef diving off the Finnish southern coast, with Dogfish, seals and dense Sea Anemone life observed across the sites.
6Brackish Baltic water with a dedicated wreck park, reefs, and sites for all levels, accessible by both shore and boat near Kirkkonummi.
5Five boat-access wreck and reef dives in the outer Baltic archipelago south-west of Turku, ranging from beginner shallows to advanced deep wrecks.
Monthly water temperature across Southern Coast & Archipelago's sites, from satellite sea-surface data corrected for depth. The band shows the site-to-site spread.
Water temperatures are at their lowest in late winter and climb gradually through spring and early summer, peaking in September before dropping sharply through autumn. The warmest months draw the most diving activity, though cold-water exposure remains a constant across all seasons. Divers should plan for variable visibility and dress for truly cold conditions regardless of when they visit.
36 operators
1 more site to explore
Water temperature around Southern Coast & Archipelago ranges from about 2°C in February to 14°C in September, based on satellite sea-temperature data for its dive sites.
In the warm season (about 14°C) a 7mm or semi-dry suit is comfortable in Southern Coast & Archipelago; in the coldest months (about 2°C) step up to a drysuit.
Fin maps 25 sites in Southern Coast & Archipelago (25 scuba diving sites), organised into 3 areas.
Across Southern Coast & Archipelago's dive sites, June, July and August are most often reported as the best months to visit.
Dogfish, Righteye Flounder, and Sea Anemone are the most consistently observed species across sites in the region. Herring appear occasionally, and there are observation-backed records of Gray Seal, Conger Eel, and Wrasses, though these are less frequent. European Common Cuttlefish and Crab have also been recorded.
Some sites are rated for beginners, including the Kronprins Gustaf Adolf wreck in the Helsinki area and the Keulakuvahylky in the Turku Archipelago. However, the majority of sites are rated intermediate or advanced, and all require readiness for cold water. Divers new to cold-water diving should select sites carefully and consider guidance from one of the many local operators.
Helsinki has the largest number of sites and a mix of wrecks and reefs, including both boat and shore entries. Porkkala focuses on deeper wrecks, such as the Klaus Oldendorff, that call for intermediate skill and cold-water experience. The Turku Archipelago offers a smaller selection of sites including wrecks at moderate depths, with some suitable for less experienced divers.
The vast majority of sites in the region are boat-access only. Shore entry is available at a small number of sites, including Raimo Ragnar in the Helsinki area. Numerous local operators, including DiveHard, Arctic Divers Dive Center, Sampo Dive, and Stay and Dive Finland, provide guided boat trips and can arrange access to sites across all three sub-areas.
