Lübeck is an old venerable Hanseatic city. But Lübeck is not just a city with a lot of history, brick art and many impressive churches. Lübeck is also a city with a lot of lively life, streets with beautiful renovated houses and many attractive shops (Marzipan too of course).
The Holster Tor is certainly a highlight and a hike along the harbor is simply lovely.
It´s not a modern city with just a few patches of history.
I have seen also Wismar and Stralsund but Lübeck clearly is the queen of the Hanseatic cities.