Hamburg is said to have even more bridges than Venice - and one reason are definitely all those fleets.
A Fleet is a Hamburg city canal - and the city is full of those canals. You can go on a Fleet Fahrt - a canal cruise or enjoy one of the cafés that are built on floating pontons or just walk across those hundred of bridges...
Whichever way you do it, you will surely get to like those fleets.
The city looks so nice in the old waterhouse quarter and the little canals. In fact, half of the city surface is made up of green or waterways.
Hamburg is also one of the greenest cities, with many parks, as Alster Park (with Alster Lake too. I had seen squirrels climbing on the trees there).
Make a visit to the Ohlsdorf cemetery (2nd largest in the world!) and the zoo (with over 2.000 animals!).
There are some small restaurants on the lake side(in the white arcade).
I always love open-air restaurants or Cafe very much...