Great question — answering as the UphillTech team:
Yes, there is! And it's well worth doing! Almost all the commercial river tours leave from the piers at Landungsbrucken, which is on the S-Bahn just south of the city centre. Also leaving from there are a number of local ferries that are part of the HVV network , which accept normal HVV tickets including day tickets : The quieter option is to take the 72 or 73 boats, which leave from the east end of the Landungsbrucken piers, which take you a short way across the river. If you're in a hurry, these are the ones to go for If you have more time, head to pier 1 and pick up the 62 ferry. On weekends, just look for the huge scrum, as there's no proper queues... Ferries are roughly every 15...
Full answer by Gagravarr: https://travel.stackexchange.com/a/19823 (CC BY-SA 3.0).
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