Viterbo is a city and comune in the Lazio region of Italy, the capital of the province of Viterbo. It conquered and absorbed the neighboring town of Ferento in its early history. It is approximately 80 kilometres north of GRA on the Via Cassia, and it is surrounded by the Monti Cimini and Monti Volsini. The historic center is surrounded by the medieval walls of Viterbo, which are still mainly intact, built during the 11th and 12th centuries.