[4] Some Shias believe that Husayn's head (ra's mubarak) is buried on the grounds of the mosque where a mausoleum is located today and considered to be what is left of the Fatimid architecture in the building, while some Ismaili sect of Shiites disagree with this.

Husayn's casket was unearthed and moved from Ashkelon to Cairo on Sunday 8 Jumada al-Thani, 548 (31 August 1153).

Taken by boat to the Kafuri (Garden), the casket was buried there in a place called Qubbat al-Daylam or Turbat al Zafr'an (currently known as al-Mashhad al-Hussaini or B'ab Mukhallaf'at al-Rasul).

[14] Regarding one of the "custodians" who brought Husayn's casket to Cairo, the famous Mamluk historian of Egypt, Mohiyuddin Abd al-Zahir, wrote:[15][16] "When Salahuddin came to power he seized all the Palaces of the Aimmat Fatemiyeen and looted their properties and treasures.

Salahuddin was angered, and ordered his intelligence agents to ask him through 'third-degree-torture', but the nobleman bore the torture and repeated his previous statement that he knew nothing of any treasures.

Salahuddin ordered his soldiers to put a cap containing centipedes on the head of the nobleman, such a type of punishment was so severe and unbearable that none could survive even for a few minutes.

Finally, Salahuddin Ayyubi ordered for a tight cap full of centipedes to accomplish the result.

As a consequence, Al-Abbas' zarih was flown to Cairo and installed at Ra's al-Husayn at the Al-Hussein mosque, instead.

The mosque was then inaugurated by President Abdel-Fattah El-Sisi and 53rd Da'i al-Mutlaq of Dawoodi Bohras, Mufaddal Saifuddin in April 2022.

[7] The minaret has panel carvings of overlapping lines that create patterns called arabesque popular in Islamic Architecture.

[23] They are mechanically operated and follow the designs of those at many Saudi Arabian mosques made from steel and teflon.

[24][25] A door laden with silver and gold was built by Mohammed Burhanuddin II and installed at the site in 1986.