A canal ring is the name given to a series of canals that make a complete loop.

The Canal Ring referred to the group of corrupt contractors and their political supporters who conspired shortly after the American Civil War to defraud the State of New York by overcharging for repairs and improvement of the state's canal system. It defied an "investigation" in 1868 and for years was powerful enough to prevent interference and to defeat unfriendly candidates for office.