The Maritimes Museum is nine floors of exhibits covering everything you would ever want to know about maritime commerce and ships. The most interesting part to me was the top floor that probably has over 80,000 model ships, mostly in 1:1250, many handmade, of ships from around the world, both military and commercial dating back to the first sailing vessels up through modern deep sea submersibles, container ships, tankers and of course warships.

The pic above is just one section. There are over 200' of shelves like this about 6' high. There is also a section on Wiking models who made and sold model ships beginning in the 50s as well as other manufacturers.
There are several dioramas as well in various scales including Soviets under way at sea:

D-Day:

And Pearl Harbor:

The lighting and set up isn't really conducive to taking pictures with an iphone and I was so amazed by everything that I really didn't take as many pictures as I would've liked.
Well worth an afternoon if you get to Hamburg.