If Rome is a city that is subjected 99% to the dictatorship of the automobile, in its surroundings you still can find routes and places that are relatively peaceful and a landscape of significant historical interest.
The only bike path of some length is that along the Tiber River, completed in 2005 including through the historical center. From the historical center the path takes one to the “GRA” [Grande Raccordo Anulare - the ring road around Rome. RB], to the north ending at Castel Giubileo and to the south.
Relatively short routes provide access to the ruins of Veio [an ancient Etruscan city. RB] and those of Galeria Antica [an ancient city of the Papal State abandoned at the beginning of the 19th century].
The province of Viterbo is relatively sparsely populated and offers roads that have relatively little traffic: for example, a route that goes from Montefiascone to Attigliano and passing by Ferento and Bomarzo .