Abstract: An endless filter chain for filtering a liquid, such as sewage, which flows along a drainage duct is provided. The filter chain comprises strainer elements and connecting links interconnected to allow the strainer elements to pivot about respective axes of the connecting links while maintaining a small clearance between the leading edge of each strainer element and the trailing edge of the respective adjacent preceding element while the filter chain is trained about an upper and a lower turning roller. the filter chain does not comprise conveyor chains and the strainer elements can be sized to a width where they cover practically the entire width of the drainage duct. A method and an apparatus for filtering liquid as well as a strainer element and a connecting link are provided.