The site is visited annually by at least 8 million pilgrims on average, which is estimated to increase to 20 million in years to come. Many Shī'ites believe that 'Alī did not want his grave to be desecrated by his enemies and consequently asked his friends and family to bury him secretly. This secret gravesite is supposed to have been revealed later during the Abbasid caliphate by As-Sadiq. Most Shī'ites accept that 'Alī is buried in Imām 'Alī Mosque, in what is now the city of Najaf, which grew around the shrine.