Islam has been present in the Horn of Africa since ancient times and Somalia has some of the oldest mosques and shrines in the entire continent. Having minarets is one architectural feature that makes Somalian mosques unique and distinct from other African mosques and Arba'a Rukun in Merca and Fakr ad-Din are excellent evidence of this architectural style. The massive round coral tower at Arba'a Rukun is about 13 meter high and is surrounded by multiple ordered recessed arches.