That underwater city is off the coast of Northern Japan, isn’t it?
Close, it’s off of Okinawa. There are others like it including megalithic ruins 2000’ beneath the waves off of Cuba and other relics of pre-flood times as well. There is a magnetic anomaly at one corner of Lake Vostok, 2 miles beneath the ice of Antarctica which pegs magnetometers in aircraft flying over (the thing that normally does that is a city...).