Karoo thunderstorms in the Great Karoo. The Swartberg Pass is not tarred and can be treacherously slippery after rain. It also becomes impassable after heavy snowfalls on the mountain, a not infrequent occurrence in winter. Poet Thomas Hardy wrote of the Karoo in his poem "Drummer Hodge". In "Bridge-Guard in the Karroo", Rudyard Kipling evoked the loneliness experienced by blockhouse soldiers at Ketting station on the Dwyka River while guarding the Karoo railway track, a lifeline during the South African War (excerpts). Karoo The Karoo ( ; from a Khoikhoi word, possibly "garo" "desert") is a semi desert natural region of
Karoo sediments. This exposed the dolerite sills, which were more resistant to erosion than the Karoo sediments, forming one of the most characteristic features of the Karoo landscape, namely the flat topped hills, called "Karoo Koppies". The geology of the region bears no resemblance to that of the Great Karoo (see the diagram on the left, of a NS geological cross-section through the Little and Great Karoos). The valley is an integral part of the Cape Fold Mountain Belt, with the two ranges on either side composed of extremely hard, erosion-resistant, quartzitic sandstone belonging to the 450- to 510-million-year-old Table Mountain