The Wilge River (Afrikaans: Wilgerivier, meaning "willow river") is a tributary of the Vaal River in central South Africa. This river is important as part of the Tugela-Vaal Water Transfer Scheme where water is transferred from the Tugela River basin to the Vaal River basin.
The largemouth yellowfish is present in the waters of the Wilge River, reaching quite a large size.
Its sources are about 50 km northeast of Harrismith, at the border with KwaZulu-Natal. In its upper course the river flows roughly southwestwards from its source, then westwards while bending northwards towards Harrismith, skirting the southern end of the Platberg where there is the confluence with the Nuwejaarspruit from the left.
Further north the Elands River joins its left bank. Then the Meul River and the Cornelis River join its right bank. It continues flowing in a NNW direction, being joined by the Liebenbergsvlei from the left, while passing near Frankfort and flowing northwestwards until it finally meets the Vaal at the Vaal Dam further downstream.
The Wilge River is a river in Mpumalanga and Gauteng provinces, South Africa. It is a tributary of the Olifants River.
The Wilge River has its origin about 15 km WNW of Leandra, in the highveld grasslands between this town and Springs, Gauteng. It flows roughly northwards until it is joined by its main tributary, the Bronkhorstspruit, that joins its left bank about 25 km downstream of Bronkhorstspruit town. Then it flows in a northeastern direction until it joins the Olifants about 12 km upstream from the head of the Loskop Dam reservoir.
Other tributaries of the Wilge are the Kendal and the Devon River.