"Hadag" means "The Fish" in Hebrew, but I don't think they had this in mind for these ferries, as…read moresuitable as it might seem.
The Hadag ferries take you from place to place along the Hamburg area of the Elbe river, from Landungsbrücken to Ottensen and a little further than that. These ferries are a wonderful way to see some of the harbor for on-a-budget tourists, as they essentially are bus-ships - they cost nothing more than a standard bus ride and make stops up and down the river at stations which are identical to bus stations.
Great for sightseeing, but also a wonderfully efficient way to get from place to place along the elbe.