Sayyiduna Urwah bin Mudarris (may Allah be pleased with him) said: I came to the Messenger of Allah (peace and blessings be upon him) while he (peace and blessings be upon him) was at Muzdalifah and the people were around him (peace and blessings be upon him). I said: "O Messenger of Allah! I am a man from the two mountains of Tayyi'. I have exhausted my mount, and by Allah, I did not come down at any mountain where you stood but that I stood there too. So is my Hajj valid, O Messenger of Allah?" The Prophet (peace and blessings be upon him) said: "Whoever attends this prayer with us, his Hajj is complete and he has fulfilled his rites (of removing his dishevelment)."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 14463