i am not quite sure how to word this but if u got a game with a map then u will understand this it is a cavern that only opens at dusk or dawn but it is located roughly south west still in the ashlands though if u have the map it looks like a narrow valley on the north east of red mountain if u understand that follow it all the way south and u will eventually go uphill to a clearing with a golden door called the cavern of the nerevaine.