An "alam" is a heavy ritual cross which is carried during the Ashura festival. The word "alam" means "flag" or "sign" in Arabic.
Ashura is a Muslim festival and commemorates the martyrdom of Husayn ibn Ali, the grandson of Muhammad, killed at the Battle of Karbala in Iraq in 680 CE. The festival is of particular significance to Shias.
Above you can see a teenage boy carrying the heavy alam in an act of self-mortification for the festival of Ashura in Tehran. Ashura is marked by such acts of mourning and grief with participants often beating themselves on the chest or using chains to flagellate themselves to express their sorrow and loss.
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