Geosite List Home Geosite Yukashigata Lagoon Yukashigata Lagoon This lagoon was formed after a marine transgression caused by sudden sea level rising in the post-glacial period. The sedimentation of the three rivers including the Niko-gawa River had formed this lagoon. Map Yukashigata Lagoon 33.6165726,135.9259843,14 See in the map app