1. More than 2.37 million pilgrims are taking part this year, according to official figures, compared to 1.86 million in 2016 and just 24,000 in 1941.
2. Some 18,000 civil defence employees, among tens of thousands of security personnel, are helping safeguard pilgrims, officials say. Additionally, thousands of security cameras have been set up along the pilgrimage route.
3. Twenty-five hospitals backed by 180 ambulances and more than 30,000 health practitioners have been mobilised to provide emergency services to pilgrims, according to the haj ministry.
4. Tens of thousands of air-conditioned tents have been set up to house pilgrims as temperatures climb to 44°C.
5. Around 14,000 international and domestic flights have so far transported pilgrims, according to official figures. Around 21,000 buses have also been used.
6. Around 16,000 telecommunication towers and 3,000 WiFi access pointshave been set up to serve pilgrims, the haj ministry says.
7. Eight million copies of the holy Quran and their translations as well as other religious books will be handed out to pilgrims, official figures show.
8. Saudi Arabia hopes to welcome 30 million pilgrims annually by 2030. Muslims also flock to the country for the umrah pilgrimage, which can be performed at any time of the year.
9. Around 54 million pilgrims have attended the haj over the past 25 years, according to official figures.