The Tulbagh basin (also known as the Land van Waveren) is bounded on the west by the Obiqua and Waterval mountains, on the north by the Groot Winterhoek range, and on the east by the Witzenberg.

To the south it is divided from the Breede River Valley by a shallow watershed that passes through the town of Wolseley.

The weir in the Nuwekloof Pass diverts up to 1.7 million cubic metres (60×10^6 cu ft) of water per day, which in summer can amount to the entire flow of the river.

[1] The Nuwekloof water gap created by the Klein Berg River is the only low-lying route through the mountains to the east of Cape Town, and has long been used for transport.

A wagon road was built through the kloof as early as the 1750s; today it forms part of the R46 regional route.