Ojamo Mine

Ojamo Mine is one of Finland's most unique dive sites — a flooded limestone mine near Lohja in Southern Finland that offers an extraordinary underground diving experience. The mine's crystal-clear water provides visibility often exceeding 30 metres, revealing dramatic submerged tunnels, chambers, and mining equipment left behind when operations ceased. Water temperature stays a constant 5-6°C year-round. The site ranges from accessible open-water areas to advanced overhead environments requiring cave diving certification. Ojamo attracts divers from across Scandinavia and Europe seeking an otherworldly dive unlike any natural site, combining industrial archaeology with the thrill of underground exploration.