Historic region of southern India spanning present-day northern Tamil Nadu and southern Andhra Pradesh, bounded by the Arni and Kotallaiyar rivers to the north and the Palar-Cheyyar-Veghavati rivers in the south. The name derives from the Tamil athondai, which refers to the creeper Ceylon caper (Capparis zeylanica) that grows in the region, and nadu (‘country’). The region historically comprised 24 kottams or settlements, described in Tamil Sangam literature — each variously governed by chieftainships of the early historical period, and later unified under Pallava (third to ninth centuries CE) and Chola (ninth to thirteenth centuries CE) rule. The primary urban centre of the region was the Pallava capital Kanchipuram. Under the Chola king Rajaraja I (r. 985–1014), the region also came to be known as Tondaimandalam; the mandalam (Tamil, ‘circle’) was a political unit under the Chola administration. Tondai Nadu later became part of the major Vijayanagara Empire in the fifteenth century.