Sayyiduna Ibn Abbas (may Allah be pleased with them both) said that the Messenger of Allah (peace and blessings be upon him), one day before the Day of Tarwiyah, said: "Tomorrow, if Allah wills, our stopping place will be at al-Khayf al-Ayman (the valley on the right side), where the polytheists drew lots (with divining arrows)."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 11002