In Romania, on the Black Sea, people cover their bodies with thick black mud rich in organic matter, good for the treatment of various diseases such as arthritis, skin ailments and beneficial for overall well-being. A swim in the lake gently and ecologically washes the mud off, sustainably recycling it. Residents of the region have been coming here their whole lives, while visitors from other parts of Romania and elsewhere generally come for a week or two combining specialized treatments at the sanatorium with regular visits to the lake.