Hi Suitsya
I have replied to your earlier post saying that I am also on the 4th September departure.
I have been to several places on the tour,Vaduz,Bregenz and Lindau,on Lake Konstanz,and I have found normal footwear is fine for day to day touring. I would only think boots would only be required if you are going hiking.Sandals would be alright,the only thing is there may be cobblestones in some places. I am not a great walker,but,haven’t found anything that I wouldn’t be able to tackle.
Keith