There are several reasons why Omani forts and castles are so well-stocked with muzzle-loading cannon. First, during the age of Omani imperial expansion its forces captured many Portuguese fortified towns along the Indian Ocean rim, bringing the cannon back to Oman for local defence against the foreign invasions that had plagued the country. Second, Oman’s British allies donated many obsolete cannon. Third, the large number of damaged cannon, typically with the muzzle blown off, may be due to the importance of Oman’s harbours to merchant vessels of other nations.  The usual way for a cannon to end its working life was for the muzzle to part company with the rest of the barrel when fired one time too many. Ships often used broken cannon and other iron scrap as ballast, dumping them when enough cargo was taken aboard. Fortunately, the intact breeches and trunnions of these scrapped cannon usually contain the markings that establish their historical provenance. HAEC craftsmen have rescued many abandoned cannon, both inside forts and outside, and have cast new muzzles for the more historically important exploded cannon and welded them to the surviving part.