A river to the south of Anurādhapura. On its banks, King Cūḷābhaya built the Cūḷagallaka-Vihāra (Mhv.xxxv.13), and Vaṅkanāsika-Tissa, the Mahā-maṅgala-Vihāra (Mhv.v.113). Once, when Dhātusena was fleeing from his enemies with a thera, his uncle, the river was found to be in flood, but a nāga king took them across (Cv.xxxviii.24). Later, when building the Kālavāpi, Dhātusena dammed up the river. Cv.v.42.

It is identified with the modern Kalā-oya (Cv. Trs.i.30, n.3).3.