The mosque has a rectangular layout encompassed by an outer baked brick wall 10 meters high and 2.65 meters thick and supported by a total of 44 semi-circular towers including four corner ones. One could enter the mosque through one of the 16 gates. It has been told that featured over each entrance were several small arched windows. Between each tower, a frieze of sunken square niches with beveled frames runs the upper course of the entire structure. The mosque had 17 aisles, and its walls were paneled with mosaics of dark blue glass. The courtyard was surrounded on all sides by an arcade, the greatest part of which was the one facing Holy Mecca.
27 meters from the center of the mosque's north face stands the Malwiya Tower with its vast spiraling cone 52 meters high and 33 meters wide at the base. At the top of the tower rests a round vestibule, which is adorned with eight pointed-arched niches. It is possible to walk all the way to the top along the spiraling path. As a matter of fact, the caliph Al-Mutawakkil, often did that riding on his donkey to enjoy the view.
The minaret was partially destroyed in April 2005, when insurgents bombed the tower because U.S. troops had been using it as a lookout position. The British claim that the attacked was directed not towards the U.S. but had been done to incite Sunni-Shiite violence and further destabilize the country.
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