DescriptionAlleghenyRiverLockandDamNo.4.jpg English: LockandDam Number 4 on the AlleghenyRiver, Allegheny County, Pennsylvania, United States. Lockand Dam
DescriptionAlleghenyRiverlock 9 - panoramio.jpgalleghenyRiverlock 9 Date Taken on 4 August 2005 Source https://web.archive.org/web/20161009201213/http://www