A wire rope safety barrier comprising a plurality of line posts positioned along a roadway. A plurality of cables are attached to the line posts and extend between the line posts to define a safety barrier along the roadway. At least one of the plurality of cables is an external cable engaging an outer surface of the line posts. Each external cable is connected to the line posts by a cable holder inserted through the cable holder slot, and the cable holder has a body portion and a hook portion. Each cable holder has a locating notch at a bottom surface configured to engage with the lower edge of a corresponding cable holder slot.