Alex is a great place to meet up with people for a drink or a snack. Sit outside for a great view over the Binnenalster on one side, or watch the shoppers go by on the other.
Alex, Alster Pavillion, Jungfernstieg 54. The nearest subway is Jungfernstieg.
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It's ridiculously expensive compared to most of Hamburg and the wind off the Alster would skin you.
Is this your business?