Country/territory: Vietnam
Subnational regions: Thai Nguyen; Tuyen Quang; Vinh Phuc
Central coordinates (latitude / longitude): 21°31'59"N / 105°34'00"E (21.5333° / 105.5667°)
Area (reported): 36,883 hectares / 368.83 km² / 91,140 acres / 142.41 square miles
Altitude: 100–1592 m (330–5,220 ft)