Millions of people undertake the Hajj every year. These photos show how different the yearly Muslim pilgrimage is this year because of the pandemic.

• Over two million people from across the world visit Mecca every year to go on a pilgrimage, the Hajj, during the last month of the Islamic year.
• This year, only about 10,000 people are expected to attend, per rules set forth by the Saudi Arabian government.
• Pilgrims are expected to remain in quarantine before starting the pilgrimage and to observe social distancing during it.
• Take a look inside what many Muslims consider one of the holiest practices, now being undertaken with coronavirus-era regulations that involve putting holy water in a plastic bottle.

Ruqayyah Moynihan contributed to this report.

Approximately two million visitors make a religious pilgrimage to Mecca, Saudi Arabia, each year.

Pilgrims at Masjid al-Haram in 2018.      Mustafa Ciftci/Anadolu Agency/Getty Images

Source: Middle East Eye

Mecca is one of the holiest cities in the Islamic religion. All Muslims who are physically and financially able to do so are strongly encouraged to make the pilgrimage, the Hajj, at least once in their lifetime.

Muslim Pilgrims pray near the Mount Arafat on October 02, 2014      Dilek Mermer/Anadolu Agency/Getty Images

Source: BBC, CDC

Pilgrims usually undertake the Hajj during the last month of the Islamic year, Dhu al-Hijjah, and around the same time as Eid al-Adha. It usually takes place over several days and as the Islamic calendar is lunar and shorter than the Gregorian calendar, the dates change from year to year.

The Masjid al-Haram.      AFP/Getty Images

Source: Middle East Eye

During the Hajj, travelers take part in prayers with other Muslims from across the world. They engage in rituals like stoning a wall and walking to different spots of religious significance in "solidarity with Abraham who is seen as the father of monotheism," Dr. Ibrahim Moosa of Notre Dame University told Newsweek in 2018.

Pilgrims touch the Kaaba stone in 2018.      Mustafa Ciftci/Anadolu Agency/Getty Images

Source: National Geographic, Newsweek

Many Muslims consider the Hajj to be as much contemplative and symbolic as it is physical — a chance to repent for past sins and start afresh. According to Islamic scripture, the prophet Abraham almost sacrificed his family in a test of faith to God. The Hajj and Eid al-Adha pay tribute to this sacrifice.

Muslim pilgrims pray on a rocky hill known as Mountain of Mercy, on the Plain of Arafat, during the annual hajj pilgrimage ahead of sunrise near the holy city of Mecca, Saudi Arabia, Saturday, Aug. 10, 2019.      Associated Press

Source: Perspective in Religious Studies, Vox

This is what crowds looked like in 2012 when over three million attendees made their way to Mecca. That year saw the highest attendance in a ten-year period, according to Statista.

An aerial view of the Kaaba in October 2012      FAYEZ NURELDINE/AFP/Getty Images

Source: Statista

This year, with the coronavirus pandemic continuing to rage across the globe, the Hajj looks very different. It started on July 28 and will run to the end of the week.

Pilgrims at Masjid al-Haram in 2020      STR/AFP/Getty Images

A maximum of 10,000 pilgrims are expected to participate this year — a significant scale-back from the usual two million-strong crowd.

STR/AFP via Getty Images

Source: Al Jazeera

In a statement shared on Twitter, the foreign ministry said only those who already live in Saudi Arabia will be allowed to perform the Hajj.

A picture taken on July 29, 2020, shows the first group of pilgrims praying after they ended circumambulating around the Kaaba, Islam's holiest shrine.      STR/AFP/Getty Images

Source: Al Jazeera, Twitter/@KSAmofaEN

In 2018, the New York Times wrote that about a quarter of each year's pilgrims come from within the country.

A pilgrim and a worker in Mecca, Saudi Arabia.      STR/AFP/Getty Images

Source: The New York Times

This year, visitors are required to follow standard coronavirus-era procedures, like covering their faces, undergoing temperature checks, and remaining in quarantine before undertaking the pilgrimage.

A picture taken on July 29, 2020, shows pilgrims walking in socially distanced lines.      STR/AFP/Getty Images

Source: Al Jazeera, CNN

Al Jazeera reported that in addition to all of the previous steps, they're are also given wristbands that monitor their movements.

Hajj pilgrims in 2020.      STR/AFP/Getty Images

Source: Al Jazeera

Pilgrims can only drink holy water from Zamzam well, a holy spot located within the mosque in Mecca, if it comes pre-packaged in plastic bottles.

Pilgrims in 2019.      FETHI BELAID/AFP via Getty Images

Sources: Washington Post

They are also expected to bring their own prayer mats to limit contact with other people.

A picture taken on July 29, 2020, shows a group praying at the mosque.      STR/AFP/Getty Images

Sources: Washington Post

Devotees are prohibited from coming in any contact at all with the Kaaba — a sacred black cube-shaped structure located at the center of the Masjid al-Haram. Normally, one of the steps of Hajj involves walking about the Kaaba in a counter-clock direction, with many touching and kissing it at some point.

A picture taken on July 29, 2020, shows pilgrims walking in socially distanced lines.      STR/AFP/Getty Images

Source: Al Jazeera

Part of the pilgrimage involves visitors collecting pebbles that they throw from a bridge to symbolically fight back against evil. This year, the tiny rocks will come packaged and sanitized ahead of time.

Muslim prospective Hajj pilgrims stone the Jamarat pillars on August 12, 2019.      Halil Sagirkaya/Anadolu Agency/Getty Images

Source: Reuters, Washington Post

Photos shared by the Saudi Ministry of Media show workers sanitizing common spaces ...

Workers sanitize the common space around the Kaaba stone in July 2020.      AFP/Getty Images

... as well as the pilgrims' luggage.

Workers sanitize pilgrims' luggage.      Saudi Ministry of Media/AFP/Getty Images

About 2.5 million Muslims made the trip in 2019. The pilgrimage is a significant source of income for the Saudi Arabian government.

Muslim pilgrims circle the Kaaba, in August 2019.      Ashraf Amra/Anadolu Agency via Getty Images

Source: NPR, ACCA

In 2015, over 700 people died and 900 were injured in a stampede in Mina, about two miles away from Mecca. Journalist Khaled al-Meena told CNN that a large number of people trying to finish their rituals in a speedy manner might have been the reason behind the incident.

Iranians mourn during a funeral procession for some of the Iranian pilgrims who were killed in a stampede at the annual hajj on October 4, 2015.      Photo by NurPhoto/NurPhoto/Getty Images

Source: CNN