Sunan Ibn Majah Book 25, Hadith 138

“I departed from ‘Arafat with the Messenger of Allah (ﷺ), and when he reached the mountain path at which the chiefs would dismount, he dismounted and urinated, then performed ablution. I said: ‘(Is it time for) prayer?’ He said: ‘The prayer is still ahead of you.’ When he reached Jam’ (Muzdalifah) he called the Adhan and Iqamah, then he prayed Maghrib. Then no one among the people unloaded (the camels) until he had prayed ‘Isha’.”