The Geumgang River, one of the four major rivers of Korea, flows through Chungcheong-do before flowing into the West Sea, and its estuary is regarded as a paradise for the migratory birds, which travel about 160km to get here. Every winter, some 500,000 migratory birds of 40 different species flock to this area. This is where the whooper swan, Baikal teal, mallard, and Chinese swan last the winter, and it is an ecologically important place for water birds.

The Geumgang River estuary is surrounded by vast stretches of lands and it contains rich water and fishery resources. The dense reed field between the Geumgang River estuary embankment and Sinseong-ri reed field is a sanctuary for tens of thousands of migratory birds and an abundant feeding ground. Also, the Geumgang River estuary is the perfect place to study migratory birds in Korea, and for this reason, it is an area with high ecological value that must be preserved.