This artificial swamp were built to secure the biological habitat for a variety of organisms, such as fish, amphibians, and birds, and was achieved by planting water plants of a pussy willow, a kind of bulrush, as well as Russian iris. This is the most natural and ecological section in the entire Cheonggyecheon district. It can be enjoyed as a place to meet birds, including mallard, large egret, and kestrel, and catfish, Chinese minnow, carp, dace, minnow, and loach. This area has been designated a bird protection zone.