6% of Berlin's surface is covered by water. 3 large rivers run through Berlin. Without the Spree Berlin probably wouldn't even exist. The city of Berlin was built on the Spree which is why many important and glorious buildings can be found around the river. The Hauptbahnhof and the Parlamentsviertel are two of many magnificent examples of why you should discover Berlin by boat.
I would be glad to accompany you on your charter boat or your normal tour and supply you with interesting facts about the „water-city“ of Berlin.