We are going to stay in an apartment in Munich that a family friend owns so I don't want to get a hotel in either of these places ( can't pass up free). I would like to see the sites of Regensburg and the Christmas market in Nuremberg. ( I know there is more to do there but my priority is the Christmas market. My questions is can I do this as a day trip from Munich or would these need to be two different day trips? If we have to pick one- which wold you choose?