Over 2 million Muslims are gathered in the Islamic holy city of Mecca, Saudi Arabia, for this year’s hajj pilgrimage, or religious trip. The pilgrimage has returned to the usual level of participation for the first time since the COVID-19 pandemic began. The pilgrims made their way out of Mecca on Monday after circling Islam’s holiest site, the Kaaba. They are gathering in the nearby desert for a day and night of prayer. The pilgrimage is one of the five pillars, or central beliefs, of Islam. The Quran, Islam’s holy book, says that all Muslims who are physically and financially able should make the pilgrimage once in their lifetime. It takes place over five days. The hajj follows a path that Muslims believe their prophet Muhammad walked almost 1,400 years ago. The holy walk is seen as a uniting event for the world’s 1.8 billion Muslims. Some people spend years saving up money to pay for the trip.