There have been numerous incidents during the Hajj, the Muslim pilgrimage to the cities of Mecca and Medina, that have caused loss of life. Every follower of Islam is required to perform the Hajj in Mecca at least once in their lifetime, if able to do so; according to Islam, the pilgrimage is one of the Five Pillars of Islam. During the month of the Hajj, Mecca must cope with as many as three million pilgrims. Plane travel makes Mecca and the Hajj more accessible to pilgrims from all over the world. As a consequence, the Hajj has become increasingly crowded. City officials are required to control large crowds and provide food, shelter, sanitation, and emergency services for millions. Despite these efforts, incidents have still occurred.

Crushes and failures of crowd control

The dense, surging crowds, trekking from one station of the pilgrimage to the next, can cause a progressive crowd collapse. At densities above six to seven persons per square meter, individuals cannot move, groups are swept along in waves, individuals jostle to find breath and to avoid falling and being trampled, and hundreds of deaths can occur as a result. The Stoning of the Devil (ramī aj-jamarāt) ceremony is particularly crowded and can be dangerous. Pilgrims ritualistically throw pebbles at three walls (formerly pillars before 2004) which represent the three places where the Hadiths describes how the devil tempted Abraham. It is one of a series of ritual acts that is performed during the Hajj. Some notable incidents include:

Fires

Protests and violence

Airplane crashes related to the Hajj

Disease

Mingling of visitors from many countries, some of which have poor health care systems still plagued by preventable infectious diseases, can lead to the spread of epidemics. If an outbreak were to occur on the road to Mecca or Medina, pilgrims could exacerbate the problem when they returned home and passed their infection on to others. This was more of a problem in the past when modern medicine wasn't as advanced. One such disease, which has prompted response from the Saudi government, is meningitis as it became a primary concern after an international outbreak following the Hajj in 1987. Due to post-Hajj outbreaks globally of certain types of meningitis in previous years, it is now a visa requirement to be immunised with the ACW135Y vaccine before arrival. Every year, the Saudi government publishes a list of required vaccines for pilgrims, which for 2010 also included yellow fever, polio, and meningitis.

Middle East respiratory syndrome

, the Saudi government asked "elderly and chronically ill Muslims to avoid the Hajj this year" and restricted the numbers of people allowed into the country due to Middle East respiratory syndrome coronavirus (MERS-CoV). Although MERS-CoV was not detected among pilgrims, this does not rule out risk of the disease at Hajj. The disease, though, is only mildly contagious.

COVID-19

The spread of the COVID-19 prompted the Saudi Arabian government to discourage people from planning for the Hajj in 2020. On 21 April, the Saudis announced that there would be no public attendance at Taraweeh in Mecca or in Medina.

Notable disease outbreaks

During the 1821 Hajj, about 20,000 Meccan pilgrims died due to a cholera epidemic. The disease had started in India in 1817. Another cholera epidemic began in 1863. It started in the Ganges Delta of the Bengal region and traveled with Muslim pilgrims to Mecca during the 1865 hajj. In 1905 the El Tor strain of cholera was discovered in six pilgrims returning from Hajj at the El-Tor quarantine camp in Egypt. The 1972 Yugoslav smallpox outbreak, the last major smallpox outbreak in Europe, was caused by an Albanian who brought the disease back from Mecca. In 2009, 73 cases of H1N1, which is also known as swine flu were recorded at the final days of Hajj. 5 pilgrims died due to the virus.

Construction failures

2006 Al Ghaza hotel collapse

A concrete multi-story building located in Mecca close to the Grand Mosque collapsed on 5 January 2006. The building, the Al-Ghaza Hotel, is said to have housed a restaurant, a convenience store, and a hotel. The hotel was reported to have been housing pilgrims to the 2006 Hajj. As a result, 76 people died and 62 people were injured.

2015 crane collapse

A crane fell in the grand mosque on 11 September 2015, ten days before Hajj, causing 111 deaths and 394 injuries.

Extreme heat

Much of the pilgrimage and its rituals are performed outdoors, on foot, and by elderly people, making pilgrims more susceptible to the intense heat present in Mecca during the summer. Outdoor rituals include standing on the plain of Mount Arafat from sunrise to sunset and walking for several hours in the outskirts of Mecca on other days. Stress due to heat has been exacerbated by increases in regional temperatures induced by climate change, which Saudi researchers stated in a March 2024 study in the Journal of Travel Medicine represented an average rise of dry-bulb temperatures by 0.4 °C (0.7 °F) and wet-bulb temperatures by 0.2 °C (0.4 °F) per decade. Both are strongly correlated with increased heat stroke and heat exhaustion, and Hajj dates that coincided with Mecca's "hot cycle" in May through September, 1982–1995 and 2015–2024, led to greater risk to pilgrims. During the 1982–1995 hot cycle, rates of heat stroke and heat exhaustion peaked at 134.2 and 858.8 per 100,000 pilgrims respectively, both occurring in August 1985 where the average daily wet-bulb temperature during the Hajj was 25.1 C. The average daily wet-bulb temperatures during Hajj between 1979 and 2019 exceeded the US National Weather Service danger threshold of 24.6 C on 38 days, nearly half of which took place in 2015–2019. The study also showed that Hajj pilgrims from countries with colder average temperature were 4.5 times more likely to die than local pilgrims. Attempts to mitigate the heat include portable water stations and misting systems, as well as expansive air conditioning in the floor of the Great Mosque of Mecca and in surrounding tents. This contributed to a 74.6% reduction in heat stroke cases and a 47.6% decrease in fatality rate compared to the prior 1982–1995 hot cycle, but still represented greater rates compared to the prior cold cycle. In 2023, temperatures reached 48 C, leading to at least 8,400 pilgrims suffering from heat-related illnesses, with the actual number likely being much greater due to the number of unreported cases. In 2024, temperatures in Mecca reached above 46 C on 16 June and 52 C on 17 June. Medical personnel had to treat at least 2,764 pilgrims (among around 1.8 million total) due to heat-related illness on 16 June 2024 alone. Jordan's foreign ministry reported on 16 June that 14 Jordanian pilgrims died after suffering from heat stroke due to the extreme heat, and that 17 more pilgrims were missing. Between 14 and 19 June 2024, at least 1,301 pilgrims had died due to extreme heat in Mecca during the Hajj of 2024, with temperatures exceeding 50 C.

Other fatal events

Of the millions of pilgrims each year, many are elderly and some die of their illnesses, exacerbated in some cases by the heat and exertion (for example, in the 1927 pilgrimage season, at least 1,500 pilgrims died ).

Pickpocketing

Since 2010s, there has been an increasing number of pickpocketing cases reported to local authorities. According to the Save Madina Foundation, there were 321 victims of reported pickpocketing during the 2010 Hajj alone.

Sexual abuse and miscarriages

Female pilgrims have spoken up about sexual abuse experienced on the Hajj through a movement called the Mosque Me Too movement. Using the hashtag #MosqueMeToo, which stems from the Me Too movement which used the hashtag #MeToo, Muslim women have shared their experiences online about sexual abuse in Mecca. Many pregnant pilgrims suffer from miscarriages due to performing the hajj. In 2011, 20 pregnant women performing the pilgrimage had miscarriages due to exhaustion.

Official responses

Critics say that the Saudi government should have done more to prevent such tragedies. The Saudi government insists that any such mass gatherings are inherently dangerous and difficult to handle, and that they have taken a number of steps to prevent the problems. The fatalities in the largest tragedy in September 2015 are alleged to have been downplayed by the Saudis by as many as 1,700. One of the biggest steps, which is also controversial, is a new system of registrations, passports, and travel visas to control the flow of pilgrims. This system is designed to encourage and accommodate first-time visitors to Mecca and Medina, while restricting repeat visits. Pilgrims who have the means and desire to perform the Hajj several times have protested what they see as discrimination, but the Hajj Commission has stated that they see no alternative if further tragedies are to be prevented. Following the 2004 stampede, Saudi authorities embarked on major construction work in and around the Jamaraat Bridge area. Additional accessways, footbridges, and emergency exits were built, and the three cylindrical pillars were replaced with concrete walls to enable more pilgrims simultaneous access to them without the jostling and fighting for position of recent years. The government has also announced a multimillion-dollar project to expand the bridge to five levels; the project was planned for completion in time for the 1427 AH (Dec. 2006 – Jan. 2007) Hajj. Following the 2006 incident, the Jamaraat Bridge and the pillars representing Satan were demolished and reconstructed. A wider, multi-level bridge was built, and massive columns replaced the pillars themselves. Now, each level of the bridge allows easier and safer access to the columns representing Satan. In addition, the stoning ceremony must be carried out according to pre-determined schedules to prevent over-crowding and the attendant risks. The Jamaraat basin has been expanded from its current circular shape into an oval to allow better access to the pillars. The new arrangements provide for separate access and departure routes. However, a security breakdown is mentioned as cause for the 2015 stampede. A group of pilgrims who had cast their own stones and were returning to their camp, instead of taking the route designated for returning pilgrims, they took the route meant for those who were coming and crossed the other group of pilgrims heading straight to the jamaraat.