My family will be on Holland America Westerdaam sailing 6/30 out of Copenhagen. I have found a wealth of information on a number of different ports, but can not find anything (written in English) on Warnemunde/Rostock. I do not plan on taking the hours long (round trip) ride to Berlin, & would instead like to travel over to Rostock for the day we are in port. I heard rumors of a 'card' similar to the Tallinn Card, which gets you free/discounted admissions & transportations. Does anyone have further information on Rostock, or a reliable web page with lots of information (in English)??