Rummu

Rummu is a weird one, pure Estonian, making the best of limited resources. This one is definitely off of the traditional tourist track…
Located 45 km west from Tallinn, Rummu is essentially the remains of a disused a limestone quarry. Over the road, Murru Soviet Prison. Made the connection yet? The convicts once housed in the prison were sent to work the mine as forced labor. Nice. Following the disintegration of the Soviet Union in 1991 and Estonia declaring its independence, the story goes that the whole placed flooded causing the closure of the mine and what formed was a quarry lake. All the buildings that made the prison, including a wide range of mining machinery and equipment, are now completely submerged. 
Today, some of the former prison can still be seen on land, and some sticking out from the crystal clear lake waters. The spot has become a prime location for divers and adventurous beach goers, who come for the sunken ruins beneath the waves. You can also clamber up the limestone ‘mountains’, for truly spectacular views of the forested surrounding areas, you can see for miles and miles… 
There used to be an organised day tour you could take, but it would seem the tour operator has discontinued the tour, and whether or not you can still access the beach area I do not know.
United’s Top Tip: Hire a car and make a day of it! Take your beach towel!