I loved Meersburg! And it's possible to drive there around the lake as this is how we did it 🙂 You can get there from Constance by car as well, it just takes a bit more time.
It's a pity you only have a couple of hours as the old castle is worth visiting. It has beautiful interior as well as views from the terrace over the lake and the Alps.
Thank you for sharing!
Maybe I can manage it next time. Castles are everytime worth to visit for me.