Iin Northern Estonia, about 28 miles (45 km) from the capital of Tallinn, hides the small borough of Rummu. While few people have heard of the area, it offers a gem for divers: there’s an underwater prison in Estonia.
Mining in Rummu started in 1938, with inmates from the Rummu Prison — originally known as Murru — mining limestone and marble and living in the quarry in a prison camp. After Estonia gained independence from the USSR in 1991, the government closed the camp and abandoned the site.
While it was operating, the mine pumped groundwater out of the quarry and into the nearby town for use in farms. After it was abandoned, however, the floor of the quarry began to flood again and with it the prison buildings that had housed inmates. Today there’s an underwater city scattered across the quarry floor, making it a popular dive site.
Diving the prison
The area sits on private property and a bit difficult to access. The owners do invite divers to explore the site on their social media pages, however. The opening hours vary from day to day, so visitors should confirm them via social media or contact the owners before their trip.
Visitors will see some derelict buildings above the surface of the water, covered in graffiti here and there. Dip underwater, though, and find evidence of human inhabitation that seems frozen in time and left to slowly erode away, creating an eerie underwater museum.
Divers can enter the submerged buildings but remember — this is an overhead environment. You’ll need the correct training and experience. There are concrete sheets, lamp posts, barbed wire, tires, pots, mining equipment and other remnants of human inhabitation — some of the windows still feature bars. There’s also an algae-covered flooded forest, consisting of trees of between 10 and 13 feet tall (3 to 4 m).
The visibility here can vary widely, between 16 to 130 feet (5 to 40 m). Visibility is better when the water temperature at the bottom and the top is nearly the same. Thus, winter and mid-summer offer the best visibility. The maximum depth is around 42 feet (13 m) with the average depth between 19 to 33 feet (6 to 10 m). Water temperature ranges between 43 and 72 F (6 to 22 C).
