Viterbo is a city of 68,000 people (2017) in Lazio, a central region of Italy.
As a settlement Viterbo dates back to Etruscan times. Between around 1100 and 1300, it was one of the most important cities in Europe. By the 13th century it had 50 castles under its control. It was the place where Popes took refuge when driven out of Rome and for several decades was the seat of the Papacy. It was the scene of battles between potential invaders of Rome and papal armies. With the departure of the Papacy to Orvieto and then to Avignon Viterbo declined in importance. It was further hit by Black Death, which killed two-thirds of its population and a major earthquake in 1349. In the 20th century it was damaged by appalling Fascist-era town planning and then by Allied bombs. These days its population is about the same as it was in the 13th century, at around 60,000. Apart from its tradition its main claim to fame now is that Italy’s gold reserves are held there.
The historical centre is small enough to be visited on foot.
For longer distances you can use the local bus network, hosted by Francigena, the government company of transport in Viterbo (ordinary 90-min ticket for €0.70; ordinary 90-min ticket on board for €1.50; daily ticket for €1.55). Tickets can be found at tobacconists, and must be validated when getting on the bus.