The Meccan Pilgrimage, also known as the Hajj, is an annual Islamic pilgrimage to Mecca, Saudi Arabia. It is one of the five pillars of Islam and is a religious duty that must be carried out at least once in a lifetime by every able-bodied Muslim who can afford to do so. The Hajj is a four-day journey that involves a series of rituals, including circling the Kaaba seven times, walking or running seven times between the hills of Safa and Marwah, and standing vigil on Mount Arafat. The Arabic word for this pilgrimage is 'Hadj', which is spelled with four letters, while the shorter version, 'Hajj', is spelled with three letters.