Volume 2, Book 26, Number 728:
Narrated Usama bin Zaid:
As soon as the Prophet departed from ‘Arafat, he went towards the mountain pass, and there he
answered the call of) the prayer is ahead of you (i.e. at asked, “O Allah’s Apostle! Will you offer the
prayer here?” He replied, “(The place of) the prayer is ahead of you (i.e. at Al-Muzdalifa).”