Cape Town lies at the south-western corner of the continent of Africa. It is bounded to the south and west by the Atlantic Ocean, and to the north and east by various other municipalities in the Western Cape province of South Africa.
The Cape Peninsula is a rocky and mountainous peninsula that juts out into the Atlantic Ocean at the south-western extremity of the continent. At its tip is Cape Point and the Cape of Good Hope. The peninsula forms the west side of False Bay and the Cape Flats. On the east side are the Helderberg and Hottentots Holland mountains. The three main rock formations are the late-Precambrian Malmesbury group (sedimentary and metamorphic rock), the Cape Granite suite, comprising the huge Peninsula, Kuilsriver-Helderberg, and Stellenbosch batholiths, that were intruded into the Malmesbury Group about 630 million years ago, and the Table Mountain group sandstones that were deposited on the eroded surface of the granite and Malmesbury series basement about 450 million years ago. The sand, silt and mud deposits were lithified by pressure and then folded during the Cape Orogeny to form the Cape Fold Belt, which extends along the western and southern coasts. The present landscape is due to prolonged erosion having carved out deep valleys, removing parts of the once continuous Table Mountain Group sandstone cover from the Cape Flats and False Bay, and leaving high residual mountain ridges.[1]
At times the sea covered the Cape Flats and Noordhoek valley and the Cape Peninsula was then a group of islands. During glacial periods the sea level dropped to expose the bottom of False Bay to weathering and erosion, with the last major regression leaving the entire bottom of False Bay exposed. During this period an extensive system of dunes was formed on the sandy floor of False Bay. At this time the drainage outlets lay between Rocky Bank Cape Point to the west, and between Rocky Bank and Hangklip Ridge to the east.[1][2]: Ch2