Melkbos is well known for its wide beach, with white sand.
To the east of Melkbos are gently rolling hills, comprising rocks of the Malmesbury Group and some inliers of granites of the Cape Granite Suite. Younger unconsolidated sediments of Tertiary to Recent age underlie the flatter areas.
The Malmesbury Group was deposited about 800 Millennia ago and consist predominantly of low-grade metamorphic rock (like greywacke, quartz, phyllitic shales, sericitic schists and siltstones). As a result of that fact that the Malmesbury Group is fairly susceptible to weather, there are mostly low relief landforms. Some granitic plutons intruded the Malmesbury Group some 630 to 525 Millenia ago; and were followed by a period of about 50 Millenia during which a lot of the metamorphosed material lying over the Cape Granite Suite were removed by erosion.