Editing Karoo (section)

===Great Karoo===
The Great Karoo straddles the 30° S parallel on the west of the continent, in a similar position to other semidesert areas on earth, north and south of the equator. It is furthermore in the rainfall shadow of the Cape Fold Mountains along the western coastline.<ref name= Altas /> 
The western "Lower Karoo" (the Tankwa Karoo and Moordenaarskaroo) contain remnants of the Cape Fold Mountains<ref name=geologicalmap>''Geological Map of South Africa, Lesotho and Swaziland''. (1970). Council for Geoscience, Geological Survey of South Africa.</ref> (e.g. the Witteberg and Anysberg Mountains)<ref name= Altas /> which give it a moderate hilly appearance, but further east, the Lower Karoo becomes a monotonously flat plain. The "Upper Karoo" has been intruded by [[dolerite]] [[Sill (geology)|sills]] (see below),<ref name=McCarthy>{{Cite book |last1=McCarthy |first1=T. |last2=Rubridge |first2=B. |year=2005 |title=The Story of Earth and Life |pages=89-90, 102–107, 134–136,159–161, 195–211, 248–254 |publisher=Struik Publishers |place=Cape Town}}</ref> creating multiple flat-topped hills, or Karoo Koppies, which are iconic of the Great Karoo.

The vegetation of the Upper is similar to the Lower Karoo, so few people make a distinction between the two.

The main highway (the N1) and railway line from Cape Town to the north enter the Lower Karoo from the [[Hex River Valley]] just before [[Touws River (town)|Touws River]] and follow a course about 50&nbsp;km south of the Great Escarpment up to [[Beaufort West]]. Thereafter, they gradually ascend the Great Escarpment along a broad valley to Three Sisters on the [[South Africa#Geography|Central Plateau]] and the Upper Karoo.

Turning north from the N1 between Touws River and Beaufort West, at [[Matjiesfontein]], the road ascends the Great Escarpment through the [[Roggeveld Mountains|Verlatenkloof Pass]] to reach [[Sutherland, Northern Cape|Sutherland]], at 1456&nbsp;m above sea level, which is reputedly the coldest town in South Africa with average minimum temperatures of −6.1&nbsp;°C during winter.<ref name=Bulpin>Bulpin, T.V. (1992). ''Discovering Southern Africa''. pp. 271–274, 301–314. Discovering Southern Africa Productions, Muizenberg.</ref> Parts of the eastern [[Mpumalanga]]n Highveld do at times experience lower temperatures than Sutherland, but not as consistently as Sutherland does.<ref name=Bulpin /> Snowfalls are not infrequent during the southern winter months. The [[South African Astronomical Observatory]] has an emplacement of telescopes about 20&nbsp;km east of the town, on a small plateau 1798&nbsp;m above sea level, and is home to the [[Southern African Large Telescope]], the largest optical telescope in the Southern Hemisphere.<ref>{{cite web |url=http://www.spacetoday.org/DeepSpace/Telescopes/SALT.html |title=Deep Space Observatories: The Southern African Large Telescope |publisher=Space Today Online |access-date=2009-01-28 |archive-date=4 March 2012 |archive-url=https://web.archive.org/web/20120304193427/http://www.spacetoday.org/DeepSpace/Telescopes/SALT.html |url-status=live }}</ref><ref>{{cite web |url=http://www.physikinstrumente.com/en/news/fullnews.php?newsid=31 |title=273 Precision Actuators for the Largest Telescope in the Southern Hemisphere |date=May 2003 |publisher=Physik Instrumente (PI) GmbH & Co. KG. |access-date=2009-01-28 |archive-date=29 February 2012 |archive-url=https://web.archive.org/web/20120229214653/http://www.physikinstrumente.com/en/news/fullnews.php?newsid=31 |url-status=live }}</ref> To the north, still on the Plateau, and 75&nbsp;km north-west of [[Carnarvon, Northern Cape|Carnarvon]], seven radio dishes form part of the [[Square Kilometer Array]] which will, 2500 in total, be scattered in other parts of South Africa and Australia, to survey the southern skies at radio frequencies. Our [[galaxy]], the [[Milky Way]], one of the main targets of this enterprise, is best viewed from the Southern Hemisphere.<ref>The Great Karoo [http://www.southafrica.net/za/en/articles/entry/article-southafrica.net-the-magical-great-karoo] {{Webarchive|url=https://web.archive.org/web/20140426235000/http://www.southafrica.net/za/en/articles/entry/article-southafrica.net-the-magical-great-karoo |date=26 April 2014 }}. Accessed 2014-04-24.</ref>
The Upper Karoo is indeed an ideal site for an astronomical observatory. This is not only because of the clear skies, absence of artificial lights, and high altitude, but also because it is tectonically completely inactive (meaning that there are no fault lines or volcanoes nearby,<ref name=geologicalmap /> and no earth tremors or [[earthquakes]] occur, even at great distances).<ref> {{Cite encyclopaedia |encyclopedia=Encyclopædia Britannica Macropaedia |year=1975 |title=Karoo |volume=17 |page=60 |publisher=Helen Hemingway Benton Publishers |place=Chicago}}</ref>