Contrary to a common misconception, there are no straits at the Cape of Good Hope.
The Cape of Good Hope is a rocky headland on the Atlantic coast of the Cape Peninsula, near Cape Town, South Africa. It marks the traditional dividing line between the Atlantic and Indian Oceans (though the official hydrographic boundary lies farther east at Cape Agulhas).
Early European sailors (Bartolomeu Dias, 1488) rounded the cape seeking a sea route to Asia. The term "strait" implies a narrow passage between two landmasses connecting two larger bodies of water (e.g., Strait of Gibraltar). The Cape of Good Hope is simply a promontory; the oceans meet openly around it.