The Half-Drowned City
Illadell predates the Great Deluge and was built on a commanding vista at the upper edge of the valley.
When the Deluge came, only half the city was covered. The evolved and rebuilt city now sits partially atop its own ruins, leaving many tunnels little known or entirely unknown. Some are fully submerged; others can be reached only by small boat or by submersion.
On the water-facing side, Illadell is built atop the ruins in such a way that it appears to float upon the water.