Anawilundawa Sanctuary is one of the 6 RAMSAR wetland in Sri Lanka, The sanctuary covers 1,397ha lying between the costal line and the Negambo – Putlam railway line. This wetland consist of six large man made tanks and 3 peripheral tanks interconnected to create a complex irrigation system. The larger tanks are Pinkattiya, Maradansola, Anawilundawa, Mayyawa, Surawila and Vellawali. Today this area is very popular among bird watchers and nature lovers. During migration season a large variery of birds can be seen using this area as feeding ground as well as breeding ground.