During the thirteen years spent in orbit around Saturn before its final plunge, the Cassini probe provided more than ten thousand astrometric observations of moons. Such a large amount of precise data has allowed us to search for extremely small signals in the orbital motion of the Saturnian satellites. These signals can be linked to key physical mechanisms at play in the system, opening the doors to a new vision of the Saturn system. Using more than a century of ground-based astrometric observations, and benefiting from Cassini imaging data, we have studied the orbital motion of all of Saturn's inner and main moons, including those recently discovered by the Cassini probe. We show how astrometry has allowed us to characterize the strong tidal effects acting among the Saturnian system, while assessing the interior characteristics of several moons and their primary, including the discovery of Mimas' ocean. Updated results are presented.