A piping unit and method for efficiently arranging a plurality of optical fibers in a communication system. The piping unit includes an elongate tube having a plurality of parallel longitudinal cavities extending the length of the tube. The longitudinal cavities have a circular transverse cross-section, while the tube preferably has an approximately square transverse cross-section. Each of the longitudinal cavities is sized to mount an optical fiber within the cavity extending the length of the elongate tube. The longitudinal cavities are arranged to maximize the number of optical fibers that are mounted within the cross-section of the elongate tube. In a square tube, the cavities may be mounted in rows and columns parallel to the sides of the tube.