《汉书·志·地理志上》
路山是资水的发源地，向东北到益阳流入沅水，经过两个郡，行程一千八百里。
路山，资水所出，东北至益阳入沅，过郡二，行千八百里。
Mount Lu is the source of the Zi River, which heads northeast to Yiyang to flow into the Yuan River, passing through two commanderies and covering a distance of 1800 li.