Vilsandi is a wetland complex on the western coast of the island of Saaremaa in the Baltic Sea. It comprises shallow marine waters, coastal brackish lagoons, reedbeds and seasonally flooded coastal meadows. It includes 160 small reefs and islands, the biggest one being the island of Vilsandi. It is a very important wintering area for waterbirds, and specifically for the globally threatened Steller’s eider (Polysticta stelleri), which is found in internationally significant numbers with over 2,000 individuals recorded wintering in the Site. A total of 247 bird species have been recorded, of which 114 breed in the wetland. Several nationally threatened plants are also present in great numbers, many of which are rarely found elsewhere in the country. A visitor centre on Saaremaa provides guided tours, while a biological research station on Vilsandi provides facilities for visiting schools and scientists.