Porta San Felice could be called the “Gate of the War” (“Porta della guerra”): the gate was witness of military marches to the enemy on the West; it was the defence place against the Ghibellines enemy coalition in Modena; the famous royal prisoner Enzo (king of Sardinia and son of the Emperor Frederick II entered into the city through this gate; furious soldiers of Modena stopped at this gate after their victory against Bologna in the battle of Zappolino; and many other times enemy armies threatened the city until the beginning of the 16th century. The gate was built in the 13th century, a fortress and a drawbridge were added in 1334. Its keep was rebuilt and covered and an avant-corps to protect the drawbridge was built in 1506 and 1508. It was restored on the occasion of the visit of Napoleon in 1805 and again in 1840 when merlons were added to the top of the wall. The gate has been always very important because of its position on the main road Via Emilia. Annexed buildings were housing guards and custom officers. One of the famous moments of its history is the affair of the “stolen bucket” (“la secchia rapita”) taken by soldiers of Modena from the spring near the gate San Felice as their spoils of war after their victory in the battle of Zappolino in 1325.
Source: "Restauro delle porte di Bologna 2007-2009"