Dōkai Bay

Dōkai Bay (Japanese: 洞海湾, Hepburn: Dōkai Wan), located in Kitakyushu City, Japan, is a long, narrow inland waterway-like bay measuring five to six hundred meters wide and 13 kilometers long. In modern times, it faces heavy industrial areas and once suffered from severe pollution and water contamination, but after a long period of successful purification efforts, the water quality has improved and the ecosystem has recovered.