Up in the Lepini mountains, 410m altitude, there are two towns next to each other on two mountain tops overlooking the drained pontine marshes. The drive up there has a few stomach-turning hair pin bends, but if you can brave them, there are great rewards up at the top! Norma is the more modern of the two towns. It was established during the medieval period. Norba to the north west, however, is an ancient Roman town, now in ruins, gradually being uncovered by archaeologists. You can wander around at your leisure. There is no entrance fee, but be careful as there area is not well looked after and is rather uneven! Bizarrely, the cliff top is also used by people who paraglide, so don't be surprised when people jump off the cliff top! You can tell who they are - they are the people who are wandering around with giant backpacks on their backs.
Norba was abandoned by its inhabitants after being attacked and destroyed. They created the nearby town of Norma. It is surrounded by thick roman walls, dating back to the 4th century bc. There are ruins of two acropolis, temples and roman streets and homes. There is a museum in Norma Museo civico archeologico in Via Nazionale in Norma. It is hidden away, but if you ask locals or follow the signs you should be able to find it. The custodian is very enthusiastic and friendly. We we fortunate enough to have a private tour!
Norma has a few restaurants, the best I have found is La Piccola Fontana with beautiful views over the Pontine Plain. There is also a pizza a taglio place in the square which is very reasonable. Here you can have slices of tasty pizza, home made pasta and sit at tables on the square. A good snack.