Narrated Al-Bara:
We prayed along with the Prophet (ﷺ) facing Jerusalem for sixteen or seventeen months. Then Allah ordered him to turn his face towards the Qibla (in Mecca):-- "And from whence-so-ever you start forth (for prayers) turn your face in the direction of (the Sacred Mosque of Mecca) Al-Masjid-ul Haram.." (2.149)
USC-MSA web (English) reference: Vol. 6, Book 60, Hadith 19
Arabic reference: Book 65, Hadith 4492