Explanation

Muharram means "forbidden" since it is considered to be holy.
Muharram also marks the anniversary of the battle of Karbala.
where the Islamic prophet Muhammad's grandson Imam Hussain Ibn Ali was killed
Muḥarram is the first month of the Islamic calendar.
The tenth day of Muharram is known as Ashura
Number of days: 29-30 (depends on actual observation of the moon's crescent)