Lake Constance. It’s the largest lake in Germany (though admitted, we share it with two other countries – Switzerland and Austria). And since Lake Constance is pretty big, it even has a couple of islands, one of them being Mainau, which actually is owned by Swedish nobility. And Mainau is a place of flowers, gardens, a castle, rare and exotic plants, and a butterfly house. Reason enough, the family thought, to spend a beautiful summer day at Lake Constance and on Mainau island.