▁Car th agini ans ▁in ▁the ▁ 2 nd ▁century ▁BC , ▁occup ies ▁a ▁strateg ic ▁location ▁on ▁the ▁Mediter rane an ▁Sea . ▁It ▁remained ▁a ▁commercial ▁port ▁until ▁the ▁reign ▁of ▁Philip ▁V , ▁when ▁it ▁was ▁re develop ed ▁as ▁a ▁major ▁naval ▁base ▁alongside ▁the ▁expansion ▁of ▁the ▁Spanish ▁Navy . ▁ ▁Const ruction ▁of ▁the ▁ar sen al ▁began ▁in ▁late ▁ 1 7 3 1 , ▁and ▁was ▁completed ▁in ▁ 1 7 8 2 , ▁during ▁the ▁reign ▁of ▁Charles ▁III . ▁The ▁final ▁cost ▁came ▁to ▁ 1 1 2 ▁million ▁real es . ▁The ▁Cart ag ena ▁naval ▁base ▁was ▁a ▁major ▁industrial ▁complex ▁by ▁the ▁ 1 8 th ▁century , ▁with ▁ ▁ship y ards ▁and ▁work sh ops , ▁carrying ▁out ▁car p entry , ▁rig ging ▁and ▁black sm ith ing , ▁as ▁well ▁as ▁craft s ▁and ▁fine ▁arts ▁work sh ops ▁to ▁produce ▁ship ▁orn ament ation ▁and ▁decor ation . ▁In ▁the ▁second ▁half ▁of ▁the ▁ 1 8 th ▁century , ▁ 2 1 ▁ships , ▁ 1 7 ▁fr ig ates ▁and ▁more ▁than ▁fifty ▁brig s , ▁x eb ec s , ▁h ul ks , ▁g alle ys , ▁etc . ▁were ▁built ▁there , ▁as ▁well ▁as ▁a ▁large ▁number ▁of ▁smaller ▁vessels . ▁The ▁Ar sen al ▁employed ▁several ▁thousand ▁people ▁in ▁the ▁construction ▁and ▁the ▁maintenance ▁of ▁the ▁units ▁of ▁the ▁Spanish ▁Navy . ▁ ▁The ▁Naval ▁Base ▁was