on a cruise ship going to Lubec Germany what is worthwhile doing near there for a day?
Try Googling-- Lubeck Germany (note spelling) for tourism ideas.
My introduction to Germany was Lübeck when I arrived in Travemünde. Lübeck is a great walking city, alot more signs pointing the way now than it was over forty years ago. The Altstadt is worth seeing.
As to "near there," how far away? Two places I would recommend, one in case you want to see a big city, is Hamburg. If it's a small town you want to see without the flood of tourists (except German ones), then I suggest Lüneburg, ca one hour from Lübeck. That town came through the war undamaged, was occupied by the British easily in their dash for Hamburg. I find Lüneburg and what it has to offer a lovely town.
- see the old town, which is a World Heritage Site
- visit the churches, which were the model for all churches in the Baltics
- buy some Marzipan at Niederegger
- have a meal at the Schiffergesellschaft (brotherhood of captains) Link
- see the Buddenbrook house
- see the Passat, one of the famous Flying P-Liners
If people can spend 2 days in Rothenburg odT it's certainly possible to spend one day in this historically much more important, and much bigger, city. ;-)