overview opening hours A man-made water reservoir built right next to the Berounka River has a natural filtration system, where the water is cleansed by bioactive zones without resorting to chemicals. opening hours may—september mon, tue, wed, thu, fri, sat, sun 10:00—18:00 more about opening hours Source: http://biotopradotin.cz opening hours may—september mon, tue, wed, thu, fri, sat, sun 10:00—18:00