The great divide of the ninth floor — city side and high elf side — and the water Signet's palace sits on.
Carl and Princess Donut spend the chapter moving northeast through the jungle, skirting the river by about a mile and staying on the city side, where the remnants of buildings show occasionally through foliage that has swallowed them completely.
The river is the floor's basic partition. Lucia Mar is marked on the The Hunter Territory Map not far away but on the high elf side, out of easy reach. One of Signet's Bush Elves remarks that it is odd to see one of Mongo's kind on this side of the river at all, and stranger to see one so well behaved. And the river is where the war is going: the Naiad Confederacy holds the former river palace of the Naiad, renamed Fort Freedom, the fortress the chapter ends by committing everyone to assault.
A broad jungle river running through drowned ruins and dense foliage, dividing the city side from the high elf side, its banks steaming after rain.
The ninth floor's dividing line and the site of the naiad palace at the center of Signet's war.