Hamburg’s Altstadt (oldest part) consists of the area between Alsterfleet, Zollkanal and the railway tracks of Central Station.
Speicherstadt (warehouse area) is no longer part of the Altstadt since the modern Hafen-City began to be constructed. Altstadt does not have a noteworthy number of timbered houses any more like Rotenburg o.d. Tauber and Celle. There are, however, little remnants of the past that have survived the centuries. Most and foremost it is some street-names that point to the past and Hamburg’s history.
Then there is the “Kontorhausviertel” such as Chile-Haus, which is closely connected with the construction of the warehouse-district; there is the downtown area as well as the four parish-churches of St. Peter, St. Nicolai, St. Katharinen and St. Jakobi with its world-famous organ. And, of course, there is the beautiful “Rathaus” (town hall) with its magnificent neo-Renaissance frontage.

Hamburg-Altstadt on Wikipedia