فَأَيْنَ تَذْهَبُونَ
Then where are you going?
The question is not seeking a geographic destination. It functions as an admonition about straying: ayna ordinarily asks where, but here departure from the right way is expressed through the imagery of going somewhere.
A place-name is not the sought answer. The proper response is for the audience to recognize the unsound direction of its conduct or reasoning.