On the eve of Arbaeen, September 17, huge crowds of pilgrims visited the holy shrine of Imam Hussein (AS), the third Imam of Shia Muslims, in the Iraqi city of Karbala.

The Arbaeen pilgrimage is one of the largest religious gatherings in the world. It comes 40 days after Ashura, the martyrdom anniversary of Imam Hussein, the grandson of Prophet Muhammad (PBUH).