Pistoia Cathedral or St. Zeno's Cathedral is the main religious building in Pistoia, located in Piazza del Duomo in the city center, the seat of the Bishop of Pistoia and where dozens of the main religious rites of the Tuscany region are held. The cathedral was probably built in the tenth century AD, and historians believe that because its facade was built in the amazing Romanesque style. Through the ages, the city's rulers added modifications to the cathedral, but it retained its beautiful general character.