remains of this culture have been exposed at Bhirrana. This culture is characterised by structures in the form of subterranean dwelling pits, cut into the natural soil. The walls and floor of these pits were plastered with the yellowish alluvium of the Saraswati valley. The artefacts of this period comprised a copper bangle, a copper arrowhead, bangles of terracotta, beads of carnelian, lapis lazuli and steatite, bone point, stone saddle and quern. The pottery repertoire is very rich and the diagnostic wares of this period included Mud Applique Wares, Incised (Deep and Light), Tan/Chocolate Slipped Wares, Brown-on-Buff Wares, Bichrome Wares (Paintings on the exterior with black and white pigments), Black-on-Red Ware and plain red wares. Period IB: Early Harappan Culture The entire site was occupied during this period. The settlement was an open air one with no fortification. The houses were built of mud bricks of buff colour in the ratio of 3:2:1. The pottery of this period shows all the six fabrics of Kalibangan - I along with many of the Hakra Wares of the earlier period. The artifacts of this period include a seal of quarter-foil shape made of shell, arrowheads, bangles and rings of copper, beads of carnelian, jasper, lapis lazuli, steatite, shell and terracotta, pendents, bull figurines, rattles, wheels, gamesmen, and marbles of terracotta, bangles of terracotta and faience, bone objects, sling balls, marbles and pounders of sandstone. Period IIA: Early Mature Harappan Culture This period is marked by transformation in the city lay-out. The entire settlement was encompassed within a fortification wall. The twin units of the town planning; Citadel and Lower Town came into vogue. The mud brick structures were aligned with a slight deviation from the true north. The streets, lanes and by-lanes were oriented in similar fashion. The pottery assemblage shows a mixed bag of Early Harappan and Mature Harappan forms. The artifacts of the period included beads of semi-precious stones (including two caches of beads kept in two miniature pots), bangles of copper, shell, terracotta and faience; fishhook, chisel, arrowhead of copper; terracotta animal figurines and a host of miscellaneous artifacts. Period IIB: Mature Harappan Culture The last period of occupation at the site belongs to the Mature Harappan period with all the characteristic features of a well-developed Harappan city. The important artifacts of the period consisted of Seals of steatite, bangles of copper, terracotta, faience and shell, inscribed celts of