Merenalainen kaupunki was released in the year 1965。Merenalainen kaupunki is also called as The City Under the Sea, War-Gods of the Deep, Stadt unter dem Meer, Stadt im Meer, Piratbyen under havet, Ciudad bajo el mar, City in the Sea, A Cidade Submarina, 20.000 leghe sotto la Terra。

Set on the Cornish coast in 1903, the film features a group of people discovering an underwater society of smugglers who never age living in a lost underwater city along with their gill-man slaves.