At the workaday zone of Mergellina at the western end of the harbor, the fishermen bring their morning catch into Porto Sannazaro.
There is no fishing in Porto Sannazaro. 
mnli hypothesis: There is no fishing in Porto Sannazaro.  premise: At the workaday zone of Mergellina at the western end of the harbor, the fishermen bring their morning catch into Porto Sannazaro.