Finding the City of Truth

I am not the originator of the following, but saw it once years ago.  It is an exercise in logical thinking.  See if you can solve it.  The best answer is not some convoluted thing that only a lawyer can understand.  The situation follows:

A traveler is seeking the City of Truth where all inhabitants ALWAYS tell the truth, but wants to avoid the City of Lies where the residents ALWAYS lie.  He comes to a fork in the path and knows that one way leads to the City of Truth and the other way to the City of Lies.  A man, a resident of one of the two cities is standing there and will respond to any ONE request, but only in keeping with his nature either as a truth-teller or as a liar. 

What simple request can the traveler make that will reveal with certainty the way to the City of Truth?  Choose wisely and just FOUR words will do the trick. 

A few hints:  It would be easy to find if the person tells the truth or lies.  He could ask, for example, “Are you alive?”  If he is from the City of Lies, he will have to say “No.”  But what good would that do in determining which way to go.  Remember, no follow-up requests are allowed—just one. 

So analyze any solution you suggest to see if it will actually tell the way to the City of Truth.

After a few days, I plan to revise this posting so that the answer is revealed.  But if you can’t wait, e mail your solution to Elton4562@Yahoo.com.  I’ll tell you if I think you got it right and why.  

Elton