The river is approximately 845 statute miles (1359 km) long, and virtually cuts the island into two distinct segments; Califia lies north of the river, while Gallia, Forriedor, and the Ivalician Federal District lie to the south. As such, the Dorvaulder is Ivalice's most important natural boundary after the Atlantic Coasts defining the island itself. The river is an important economic artery, and hundreds of ships pass along the river each year. Its primary tributary, the Aerelon River, is critical to the Midlands Crescent region of Forriedor, connecting the industrial heartland of the state between New Manchester and Clellinon with the capital, Londinium.