Mount Sion (Irish: Cnoc Sion) is a Gaelic Athletic Association club located in Waterford City, County Waterford, Ireland, founded by Brs O'Connor and Malone, teachers in the above school. Although technically separate from the school, the club still maintains a close relationship with the school, sharing the same sports facilities in the city. The club fields teams in both the Waterford Hurling and Gaelic football championships and has had many famous players, including John Keane, Philly Grimes, Tony Browne and Ken McGrath.