Núi Cốc Reservoir (Vietnamese: Hồ Núi Cốc) is an artificial lake, approximately 25 kilometres (16 mi) west of the city of Thái Nguyên in Thái Nguyên Province, Vietnam, in Tam Đảo National Park.

[1][2][3] The lake is located in the scenic backdrop provided by the Coc Mountain (Vietnamese: Núi Cốc).

The northern bank has many upscale guest houses built on slopes of the hill amidst green trees, known as keo la cham.

The Tourism Trade Union Joint Stock Co. has invested VND 15 billion in this eco-tourism park in an area of 1 hectare (2.5 acres).

[1] Other attractions in the park are: a 'Fairy Tale House Underworld and Water park' with a total area of about 6 hectares (15 acres); an artificial cave system, a large fish statue; in one of the large islands of 89 islets in the lake Vietnamese traditional culture is on display with 2061 cultural and historical items, which include the Bodhisattva of Compassion with thousands of hands and eyes.

The flora found in the lake precincts are Rhodomyrtus tomentosa, Melastoma candidum, Cratoxylon spp.

Despondent, broken-hearted and pining for his lover, Coc played the flute to call Cong to his room, but she was not allowed to leave the house to meet him.

Her love was sincere and loyal, and she cried so much that it resulted in her dying and transforming into tears, which seeped to the ground and started flowing as a stream called the 'Cong River' (which feeds the lake) in search of her fiancé.