"Prime" is relative – the Baltic sea is rather cold and the only reason I sometimes go there is because it's just about two hours and 30 Euros away. When I have more than a weekend, a flight to the Mediterranean is preferred. Plus this is on a island and that'd be another hour or so (ferry or detour).
Berlin is probably the only city for which it's a somewhat attractive destination, but I don't see the rich people here going for it. Flying to italy take only a bit longer, or, if it needs to be close, there are quite a few opulent estates from the 16th to early-20th century within an hour of the city center, quite often with direct access to one of the many lakes.