The city sits over a large fault line that runs across the former kingdom and into what was the western part of Valdemar at that time. A hole was punched in the fault during the Mage Wars, leading to extreme instability in the fault. The Tayledras, who once lived where Highjorune is now situated, left an active Heartstone in place, anchoring a spell that not only stabilizes the fault, but is slowly repairing the mage-wrought damage.