"Here I am Allah, answering your call," chanted a chorus of pilgrims as the huge crowd moved on foot or by bus along the road linking Mecca to Mina, which has been transformed into a vast site of fireproof tents.
The journey began mid-morning, proceeding with calm and without major incident amid mild weather conditions.
The faithful will spend the day here in prayer and meditation. They will also take part in the weekly Friday prayers, which this year coincide with the huge religious gathering in Mina.
The men are clad in a two-piece seamless white cloth in keeping with tradition, while women are fully covered except for the hands and face.
The journey to Mina is taking place amid the tightest security measures, imposed by the Saudi Arabian authorities to ensure the safety of the near two million pilgrims.
The authorities have warned that they will not tolerate any attempt to undermine security during the Haj.
Before dawn on Saturday, the faithful will move towards Mount Arafat for the culmination of the Haj, symbolising the Final Judgement at the scene of the Prophet Mohammed's (PBUH) last sermon 14 centuries ago.
The faithful will then return to Mina to sacrifice an animal, generally sheep, marking Eidul Adha, or feast of the sacrifice, celebrated on Sunday.
They will spend two more days in Mina to take part in a symbolic stoning of the devil.