Karoo Karoo The Karoo ( ; from a Khoikhoi word, possibly "garo" "desert") is a semi desert natural region of South Africa. No exact definition of what constitutes the Karoo is available, so its extent is also not precisely defined. The Karoo is partly defined by its topography, geology and climate, and above all, its low rainfall, arid air, cloudless skies, and extremes of heat and cold. The Karoo also hosted a well-preserved ecosystem hundreds of million years ago which is now represented by many fossils. The Karoo formed an almost impenetrable barrier to the interior from Cape Town, and the
Karoo in the east, where the Langeberg range (arbitrarily) starts to be called the Outeniqua Mountains. The Little Karoo can only be accessed by road through the narrow defiles cut through the surrounding Cape Fold Mountains by ancient, but still flowing, rivers. A few roads traverse the mountains over passes, the most famous and impressive of which is the Swartberg Pass between Oudtshoorn in the Little Karoo and Prince Albert on the other side of the Swartberg mountains in the Great Karoo. Also, the main road between Oudtshoorn and George, on the coastal plain, crosses the mountains to the south via