The James River Gorge is a water gap created by the James River in Central Virginia. The Gorge is deep as measured from Highcock Knob to the James River and is approximately long. The James River forms in western Virginia near the border of West Virginia and initially flows south through the ridge and valley province of the Allegheny Mountains, turning northeast when it comes to the western edge of the Blue Ridge Mountains near Buchanan, Virginia. From Buchanan the river flows along the base of the Blue Ridge Mountains until it joins the Maury River near the town of Glasgow and then it turns southeast and begins its descent over the Balcony Falls rapids and through the James River Gorge. The rocks of the gorge are metamorphic in nature with the oldest exposed outcrops being from the Proterozoic Era.