▁for ▁nearly ▁ 9 0 0 ▁years , ▁and ▁hydro elect ric ▁generation ▁in ▁the ▁present . ▁ ▁Cir ca ▁the ▁year ▁ 1 1 8 8 , ▁the ▁architect ▁Alberto ▁Pit ent ino ▁designed ▁a ▁series ▁of ▁d ams ▁to ▁flo od ▁the ▁sw amp y ▁area ▁North ▁and ▁West ▁of ▁the ▁medieval ▁city ▁of ▁Mant ua . ▁This ▁set ▁of ▁walls ▁create ▁the ▁L ago ▁Super iore . ▁Use ▁of ▁the ▁kin etic ▁energy ▁of ▁the ▁water ▁flow ▁was ▁directed ▁through ▁at ▁least ▁ 1 2 ▁dozen ▁mill s , ▁each ▁named ▁after ▁a ▁separate ▁apost le , ▁built ▁along ▁the ▁dam . ▁Work ▁continued ▁on ▁the ▁structure ▁until ▁ 1 2 3 0 . ▁▁ ▁During ▁the ▁wars ▁of ▁the ▁Vis cont i ▁and ▁Gonz aga ▁in ▁the ▁ 1 4 th ▁century , ▁one ▁effort ▁was ▁to ▁try ▁to ▁re channel ▁the ▁M inci o , ▁but ▁the ▁effort ▁failed ▁and ▁a ▁bre ached ▁dam ▁cause ▁a ▁portion ▁of ▁the ▁structure ▁to ▁be ▁dam aged , ▁leading ▁to ▁the ▁construction ▁of ▁a ▁rounded ▁dam ▁called ▁della ▁ro ta . ▁ ▁At ▁the ▁north ▁end ▁of ▁the ▁bridge , ▁circa ▁ 1 5 3 0 , ▁Feder ico ▁II ▁Gonz aga , ▁Duke ▁of ▁Mant ua ▁commission ed ▁from ▁Giul io ▁Rom ano ▁construction ▁of ▁a ▁for tr ess , ▁Port a ▁Giul ia , ▁def ending ▁access ▁to ▁the ▁city . ▁It ▁was ▁restored ▁in ▁ 1 7 5 2 ▁by ▁the ▁engineer ▁Antonio ▁Maria ▁Az z al ini