Shaykh Abdul Muhsin, “The person who prays must pray towards the Qiblah ie al Ka’bah. If the person is resident, or you’ve the ability to know the Qiblah, like you are in a city then it’s an obligation. If you have the ability to ask but you didn’t ask then the prayer is invalid if you prayed towards the wrong direction.”
[Taken from the lessons on “Conditions, Pillars and Obligation of Salah – Shaykh ul Islaam Muhammad bin Abdil Wahhab رحمه الله Explanation by Shaykh Abdul Muhsin al abbaad حفظه الله Taught by: Abdulilah Lahmami]