The Overberg ("over the mountain") is the region southeast of Cape Town across the Hottentots Holland Mountains. Once over Sir Lowry's Pass on the N2, the landscape opens into rolling wheat fields, canola, and eventually the dramatic Cape coastline.
Hermanus is the Overberg's main town and one of the world's best spots for land-based whale watching — southern right whales come to calve in Walker Bay from June to November. The cliff paths overlooking the bay are free and you can watch from directly above the whales.
Agulhas, at the very southern tip of the African continent (not the Cape of Good Hope, which is a common misconception), is worth the drive for the lighthouse and the official marker at the meeting of the Atlantic and Indian oceans.
The Overberg is easy as a day trip from Cape Town, or as a night or two on the way to the Garden Route.