During the Ifriqiyan period, the main base and arsenal of the Fatimid navy was the port city of Mahdiya, founded in 913 by al-Mahdi Billah. Apart from Mahdiya, Tripoli also appears as an important naval base; while in Sicily, the capital Palermo was the most important base. Later historians like Ibn Khaldun and al-Maqrizi attribute to al-Mahdi and his successors the construction of vast fleets numbering 600 or even 900 ships, but this is obviously an exaggeration and reflects more the impression subsequent generations retained of Fatimid sea-power than actual reality during the 10th century. In fact, the only references in near-contemporary sources about construction of ships at Mahdiya are in regard to the scarcity of wood, which delayed or even stopped construction, and necessitated the import of timber not only from Sicily, but from as far as India.