There is described a retroreflective road surface marking tape material of the type having retroreflective systems secured at its upper surface layer, and including new retroreflective systems of elongated and cross-sectionally uniform configuration. There is also described method for forming said material, including preforming the elongated transparent elements of said systems from cutting into pieces an extruded stock transparent material and preferably arranging the resulting elongated systems perpendicularly of the length of the tape of a wider strip adapted to be longitudinally severed in tapes of the desired width.