River Brienne

The River Brienne begins its 600 miles journey to the sea amongst the fast-flowing mountain streams of the Vaults. From here it flows almost directly westward through the wild domain of the Loren Forest, and the largest single Wood Elf realm. The river assumes considerable proportions within the Loren Forest, fed by numerous forest springs and small rivers flowing from the Irrana mountains to the south. By the time it reaches the city of Quenelles, it is over 100 yards wide, and the bridges at that city are divided into spans supported by piles sunk into the bed. Quenelles lies 800 miles from the sea, but is still accessible to nromal sea-going vessels, although the river above Quenelles is more shallow, and transport is normally by flat barges. From here to the sea, the river is swollen by numerous large tributaries, so that at its mouth it is several hundred yards wide. The city of Brionne lies on the northern bank, whilst the south is marshy and uninhabited.

Source
Warhammer Fantasy RPG 1st Edition -- pg. 274