Warmup solution, Challenge 1, Spring '05

Ask the native, "Which fork goes to your village?" Without knowing whether he lied, you can be certain that the fork he indicates is the one you want.

A somewhat less-elegant solution that is nevertheless worth thinking about is the following: point to one of the forks and ask, "If I were to ask you if this road goes to the Truth Tellers' village, would you tell me "yes"? A Liar would tell you the wrong answer if you asked him, but he must also lie about what that answer would be. He will therefore answer "yes" if the road you point to goes to the Truth Tellers' village, and "no" otherwise, just as a Truth Teller will do.