The James River, located entirely within the Commonwealth of Virginia, flows for approximately 348 miles (560 kilometers) from its mountain headwaters to the Chesapeake Bay, extending to about 444 miles (715 kilometers) when including the Jackson River source. Its extensive watershed drains a catchment basin covering roughly 10,432 square miles (27,020 square kilometers), widening significantly as it approaches the Hampton Roads harbor area where it spans multiple miles across.