river, east-central Andhra Pradesh state, southern India. The Gundlakamma rises in the Nallamalla Range of the Eastern Ghats. After crossing the mountains, it enters the plains and flows in a northeasterly direction past Markapur to the Coromandel Coast of the Bay of Bengal (Bengal, Bay of), into which it empties 12 miles (19 km) east of Ongole, after a course of 140 miles (225 km).