Baden Baden, Colmar, Freiborg, Titisee, and mostly Black Forest day excursions. Therefore, as "NJUPINTHEAIR" thankfully highlighted, Karlsruhe is a better location.

The lounge is a plus for Heidelberg Marriott, but it will be ok to forego if Karlsruhe RN offers decent complementary breakfast as the hotels does offer free minibar daily.

Frankly, what's bothering me is the parking fee and I was wondering if I'm able to find cheeper or free parking near the hotel (fyi: my stay will span over a weekend).

Room configuration and possibility of mega suite upgrade is also a deciding factor. With a family of 5, it would be a big plus if I'm upgraded to a big/multi-room suite instead of paying for two standard connected rooms.