RIFF, The (Er-Rif). A name given to the mountain region bordering the north coast of Morocco from Ceuta eastward nearly to the borders of Algeria and included in the Atlas system. The rugged coast, the principal projection of which is Cape Tres Forcas, is almost without harbors. The inhabitants are pure Berbers in blood. In the French conquest of Algeria they were not molested, and they are said to live in a state of chronic revolt against the Sultan of Morocco. They were formerly noted for piracy. The people understand or speak Arabic only to a very slight extent, Shleh or Shluh being their native tongue. They are said to be untrustworthy.