The Realm of Astoria
Astoria is made up of a 10x10 hex grid. Of that grid, 15 hexes are mostly water. Hex 31, while being almost entirely water has a settlement on it (Ferryton specifically) and will likely be traveled frequently. Thus, it makes sense that 31 uses a water based encounter table.
Figure 1. The Hexmap of Astoria
While every dungeon or encounter has a "canonical" hex (denoted in bold,) they will also have other possible locations. This allows the same group to explore Astoria multiple times without spoiling it for themselves.
Towns
These are 11 settlements in Astoria. 2 of them start inhabited, the rest have prerequisites that must be achieved before NPCs will begin settling there.