Hi there Amy, the airport is less than 10 miles away from the port of Hamburg, and even allowing for heavy traffic in the city, the journey shouldn't take more than about 30 minutes.
There is also a very frequent train service between Hamburg & the airport, which again takes about half an hour.
Hope this helps,
Alan & Katrina
Last Cruise: Minerva April 2015
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Then: P&O Oriana October 2015
and : Queen Victoria January 2016
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