Diving into the waters in Rummu in northern Estonia, you will find an underwater jail. The then jail has become one of the world’s most famous dive sites. /VCG Photo

Called Murru, the jail was previously a limestone quarry. Convicts who had committed the worst crimes, like murder or raping, would be escorted to the quarry and were used for mining. /VCG Photo

In 1991, underground waters flooded the quarry because workers had stopped draining the water. /VCG Photo

Right now the area is a crystal clear lagoon yet, and divers have to contact a local dive store for the permit to enter the area. /VCG Photo

According to Karina Oliani who is a filmmaker and diver, the color of the lagoon varies from bright green to turquoise which makes the location attractive for shots. /VCG Photo