The twelve artillery pieces are installed on concrete bases before the façade of the old Sailors Training Barracks. The cannons belong to the museum's permanent exhibition. These pieces, weighing hundreds of kilos, have been decommissioned from the Spanish fleet. These twelve pieces are the result of a collection of naval guns from the 18th and 19th centuries from different origins, as can be seen from the coats of arms engraved on their barrels, mostly 24-pounder long guns and 36-pounder long guns. One of the guns belonged to the British Navy and was taken after the reconquest of Mahón, on the barrel of the cannon can be seen the coat of arms of King George III, also it is noteworthy the 2 guns belonging to the Russian fleet that the Tsar Alexander I sold to King Ferdinand VII, to quell the Rebellion of the Provinces in South America, the coat of arms of the double-headed eagle (symbol of the Tsar) can be seen on the barrel of these cannons.