[2] Local tradition claims that Salmonsdam was named for Robert Salmond, captain of HMS Birkenhead, which sank at Gansbaai in 1852.

The river flows from northeast to southwest, starting in a gorge called Keeromskloof and spreading out lower down into a marshy area known as "Die Weivlakte".

Various smaller tributaries join the river; notably the Watervalkloof stream which passes over a series of small waterfalls called the "Zigzag Falls".

The highest point in the park is the base of the radio mast at its northeastern corner, at a height of 637 metres (2,090 ft) above sea level.

The Perdeberg peak on the northern edge of the park is one metre (3.3 ft) lower.