|This is the old Fishmarket hall: it is nearly always underwater when the Fishmarket is flooded.
In order to ease the pressure of the water on the building, the gates are opened to let the water flow through.
With a little imagination you can see the walkway leading down to the pontoon behind the back door.
Normally that walkway leads down - but when the river Elbe has this kind of high tide, the walkway runs horizontal and the pontoon rises accordingly. A very strange sight.