Horizon (Concordia) is a large chantry for all Traditions. A 10th council seat appeared with an unknown written symbol on it. The Solificati believed it meant Unity and wanted to claim it.
Horizon Chantry inside City of Concordia which is inside Horizon Realm. 30,000 people total. 15,000 in Concordia. About 150 mages. Diamond Barrier called Crystal Bastion has 9 gates & surrounds Concordia.
1453 Horizon (the realm) started forming - finishes April 1456 Horizon is designed to be a mega Horizon Realm.
See Horizon Stronghold of Hope and Castles & Covenants pg. 101