This weekend some 2.5 million people are expected to take part in this year's Hajj, the annual Muslim pilgrimage to Mecca. But this year's pilgrimage takes place against the backdrop of the Arab Spring. The Saudi government has mobilized 100,000 defense personnel to prepare for the world's largest human assembly. The Saudis say the build-up is to avoid the deadly stampedes that have broken out in previous pilgrimages. But one can't help but wonder if the democracy movements in neighboring countries is a lingering factor as well. 

Today marks the third and most important day of the Hajj, an annual Islamic pilgrimage that has drawn as many as three million Muslims to Mecca, Saudi Arabia. The four-day trip is arduous, packed with rituals and prayers. Most pilgrims begin planning for the trip up to six months in advance and set aside around $2,000 to make the journey. Some are encouraged to get in good physical shape, build their immune system, prepare a will, and go through counseling so they are mentally prepared.

Islam is in many ways an essentially green religion, with foremost ethical principles stressing the importance of protecting the Earth and living in harmony with nature. But the Hajj, which officially began yesterday, has in recent years been attracting negative attention for its environmentally unfriendly effects. What does it mean when one of Islam's holiest events leads to environmental damage?

It's the second day of the Hajj, the yearly pilgrimage to Mecca, in Saudi Arabia. 2 million Muslims from around the world typically make the trip; this year Saudi Government officials are predicting a 40% drop in the number of local pilgrims to Mecca this year because of fear of H1N1. We speak to the BBC's Shahzeb Jillani, from the middle of the Hajj, about the fears, precautions and facts about the spread of the flu at this year's pilgrimage.

As the annual hajj pilgrimage begins, we check in with BBC reporter in Mecca, Shahzeb Jilani. We also talk with the State Department’s Special Representative to Muslim Communities, Farah Pandith, about her work and whether or not she plans to make the annual pilgrimage to Mecca this year. It’s all part of our continuing series on Faith in America.