No, it is not the fantasy world Narnia, but the allegedly center of Italy: Narni. Allegedly because there is also another town supposed to be the center of Italy: Rieti. But I don't want to argue here.
There is everything you could want for an ordinary little town in Narni: a castle, a fountain, a view point, and probably some history.
And also the above sign, but like I said, who can be sure if it's true...