Abstract: An optical cable suitable for suspension beside an electrical railway or other location where an electric communication cable would be subjected to electrical interference comprises an optical cable element which is loosely housed in and extends helically throughout the length of an outer protective sleeve which has embedded in and at spaced positions around the sleeve a plurality of elongate non-metallic reinforcing members which extend lengthwise of the sleeve. Each reinforcing member has, in the member, undulations that serve to improve the mechanical bonding of the member within the sleeve and the flexibility of the cable. The optical cable element comprises a plurality of plastic tubes helically laid around a central non-metallic reinforcing member and surrounded by an outer sheath. In each of some of the tube is loosely housed a separate optical fibre.