What color are my shoes?

Say which way to the city you live in? They will both say city of truth

Which way do you live?

Simple. Which way is it to the city of truth? The liar points you to the wrong one, you know you have to go the other way, the truth teller points you the right way, you are fine.

To the civil people that asked calmly, here's my explanation. And To the simple minded people: Think about it(for a change) for a moment. Let's say the citizen is a liar. I ask him: if I asked you where I should pass to the city of truth, where would you point to? He would point to the city of truth, right? Because he would lie about the location of his own city. Then if the citizen is a honest person, he would still point to the city of truth, right? I apologize if I oversimplified.

To the daft commentators: read a book sometime

Would you want to fart in your face? The lair would have to say yes

Well to find the way to the City of Truth, I would ask the citizen "If I were to ask you which way leads to the City of Lies, which way would you point.?” because think about If the citizen is from the City of Lies, they will point to the City of Truth, because they are lying about which way leads to the City of Lies. If the citizen is from the City of Truth, they will point to the City of Lies, because they are telling the truth about which way leads to the City of Lies.