Here are the best hotels in Hamburg:
Kempinski Hotel Atlantic 72 An der Alster Hamburg
Park Hyatt Hamburg 8 Bugenhagenstr. Hamburg
Vier Jahreszeiten 9 Neuer Jungfernstieg Hamburg
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Dorint 40 Alter Wall Hamburg
Elysee 10 Rothenbaumchaussee Rotherbaum
Inter-Continental 10 Fontenay Harvestehude
Lindtner 123 Heimfelder Str. Harburg
Louis C. Jacob 401 Elbchaussee Nienstedten
Marriott Hotel 52 ABC-Str. Hamburg
Renaissance Hotel Große Bleichen Hamburg
SIDE 49 Drehbahn Hamburg
Steigenberger Hamburg 4 Heiligengeistbrücke Hamburg
I would stay at the Marriot or the Renaissance; location. The very best of all is Vier Jahreszeiten, but this one comes with a real big price tag and might send the "wrong message" to your people in Elmshorn!?