In one Czech dictionary it says that the following sentence is incorrect.
Prague belongs among the most beautiful cities in Europe.
I admit that it does not sound natural to me and I would never use it like that, but I cannot put my finger on what is wrong with it. Is it because of the "the most beautiful"?
Please note that I'm not a teacher.
No – 'belongs among' sounds odd.
Prague is one of the most beautiful cities in Europe.