You approach two talking doors. One door leads to the City of Truth, while the other door leads to the City of Liars. You do not know which door is which. You are able to ask only one question to determine which door is which. The door that leads to the City of Liars always speaks lies, while the door that leads to the City of Truth always speaks the truth. You want to go to the City of Truth. What question do you ask to determine which door leads to the City of Truth.
This riddle does not have 2 guards, You can only ask one question to determine which door to go through.
You are asking a door, the door will reply to you, But you can only ask one of the doors.
The Truth Door
The Liar Door
HINT:
Ask a question that will involve both doors.