1. Which is the longest inland river in the country?

  • Red River
  • Dong Nai River
  • Hau River
Exactly

Dong Nai River is the longest inland river in Vietnam, the second largest in the South in terms of basin, after the Mekong River. Dong Nai River flows through the provinces of Lam Dong, Dak Nong, Binh Phuoc, Dong Nai, Binh Duong, Ho Chi Minh City. If calculated from the source of Da Dang River, Dong Nai River is 586 km long, and if calculated from the confluence with Da Nhim River below Pongour waterfall, it is 487 km long. Dong Nai River flows into the East Sea in Can Gio district. Its main tributaries include Da Nhim River, Be River, La Nga River, Saigon River, Da Hoai River and Vam Co River. Its tributaries are called Long Tau River (Nga Bay River), Dong Tranh River, Thi Vai River, Soai Rap River (Soi River), etc.

2. Where does the Dong Nai River originate?

  • Lam Dong
  • Dong Nai
  • Dak Nong
Exactly

Dong Nai River originates from Lam Vien Plateau (Lam Dong). The upstream of Dong Nai River is named Dac Dung. The river meanders along the Northeast - Southwest direction, crossing the mountains to the plains in Ta Lai (Tan Phu district, Dong Nai province). The river is the natural boundary between Dak R'Lap (Dak Nong) and Bao Lam - Cat Tien (Lam Dong), between Cat Tien and Bu Dang (Binh Phuoc) - Tan Phu, between Tan Phu and Da Teh.

3. The upper Saigon River is in which province?

  • Dong Nai
  • Binh Phuoc
  • Tay Ninh
Exactly

The Saigon River is a tributary of the Dong Nai River. The 251 km long river originates in Binh Phuoc province, flows through Tay Ninh, Binh Duong, Ho Chi Minh City and then joins the Dong Nai River. The headwaters of the Saigon River are in Loc Ninh district in the north of Binh Phuoc province.

4. Which province is 'where the Red River flows into Vietnam'?

  • Lao Cai
  • Lang Son
  • Son La
Exactly

The Red River (or Hong Ha) is a river with a total length of 1,149 km originating from Yunnan, China, flowing through Northern Vietnam and emptying into the Gulf of Tonkin. In Vietnam, the Red River is 556 km long and is an important river in the Vietnamese rice culture.

The first point of contact of the Red River with Vietnam's territory is at A Mu Sung commune, Bat Xat district, Lao Cai province, the middle of the river is the dividing point of the two countries' territories. Arriving at Lao Cai city, the Red River flows completely into Vietnam's territory. To the east of Lao Cai city, the river forms the boundary between the city and Bao Thang district, passing through Bao Thang and Bao Yen, along the border of Bao Yen and Van Ban.

5. “All rivers flow to the East, except for the river… that flows to the North” which river is it?

  • Ma River
  • Da River
  • Thao River
Exactly

The Da River, also known as the Bo River or Da Giang, is the largest tributary of the Red River. The Da River is 927 km long, with some documents recording 983 km or 910 km. The main stream originates from Vo Luong Mountain, Yunnan Province, China, flowing in the Northwest - Southeast direction to join the Red River in Phu Tho. The section in Vietnam is 527 km long (some documents record 543 km). The starting point is the Vietnam - China border in Muong Te District (Lai Chau). The river flows through the northwestern provinces of Vietnam, including Lai Chau, Dien Bien, Son La, Hoa Binh, Phu Tho (dividing Thanh Thuy District, Phu Tho with Ba Vi, Hanoi). The end point is the Hong Da junction, Tam Nong District, Phu Tho Province.