Halda River is a river in south-eastern Bangladesh. It originates at the Badnatali Hill Ranges in Ramgarh Upazila in the Chittagong Hill Tracts, flows through Fatikchhari Upazila, Bhujpur Upazilla, Hathazari Upazila, Raozan Upazila and Chandgaon Thana of the Chittagong Metropolitan City, and falls into the Karnaphuli River. The 81-kilometre (50 mi) long river has a very turbulent tributary, the Dhurung River, which joins Purba Dhalai about 48 kilometres (30 mi) downstream. The river is navigable by big boats 29 km into it (up to Nazir Hat) and by small boats 16–24 km further (up to Narayanhat).