Heavy rainstorms have hampered the start of the annual Hajj pilgrimage in Saudi Arabia.
Up to two million pilgrims are expected to travel to the holy city of Mecca.
The Hajj is one of the pillars of Islam and every adult Muslim must undertake it at least once in their life if they can afford it and are physically able.
Fewer people have been expected this year because of fears that swine flu could be easily spread via the mass gathering.
Many of the pilgrims are staying in tents in the city of Mina, near Mecca.
After spending their nights in Mina, the pilgrims embark on a journey to the valley of Arafat, where they will spend the next stage of the pilgrimage.
The Saudi authorities have a quota system to keep down the numbers of pilgrims from around the world.
As well as swine flu, rain and a surge in the temporary population, Muslims in Jiddah have to face crawling traffic, made worse by the weather.
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