The region with the capital Bologna is located in the north of Italy. It extends from the Adriatic Sea in the east with the area of Romagna to the inland area of Emilia in the west. In the north, the Po River forms the border with the region of Lombardy, in the south the Apennines form the almost 300 kilometre long border with the regions of Liguria and Tuscany. The western part of Emilia was divided into the duchies of Parma and Modena, which were a constant bone of contention between the Habsburgs and the Bourbons. The name derives from the Via Aemilia, which was built by the Romans in 187 BC to connect the cities of Piacenza and Rimini. The eastern part of Romagna was part of the Papal States for several centuries. Today, the extremely fertile Po Valley produces a wide range of agricultural products. Around Modena, the famous balsamic vinegar is produced according to a centuries-old tradition. The two provinces of Reggio Emilia and Parma are home to the equally famous Parmigiano Reggiano cheese, the genuine Parmesan cheese of protected origin.