▁the ▁Great ▁Kar oo , ▁except ▁for ▁a ▁small ▁strip ▁just ▁south ▁of ▁Les oth o ▁which ▁is ▁often ▁included ▁in ▁the ▁High vel d . ▁To ▁the ▁west ▁the ▁High vel d ▁f ades ▁into ▁the ▁dry ▁sav ann ah ▁of ▁G ri qu aland ▁West , ▁beyond ▁which ▁lies ▁the ▁Kal ah ari ▁desert . ▁This ▁boundary ▁is ▁very ▁vague . ▁The ▁High vel d ▁therefore ▁en comp ass es ▁the ▁entire ▁Free ▁State , ▁and ▁an ▁ad jo ining ▁strip ▁of ▁the ▁Provin ces ▁to ▁the ▁north ▁of ▁it . ▁It ▁receives ▁between ▁ 4 0 0 ▁and ▁ 1 2 0 0   mm ▁of ▁rain ▁ann ually , ▁and ▁is ▁largely ▁a ▁flat ▁grass land ▁plain . ▁Much ▁of ▁the ▁area ▁is ▁devoted ▁to ▁commercial ▁far ming , ▁but ▁it ▁also ▁contains ▁South ▁Africa ' s ▁largest ▁con urb ation ▁in ▁G aut eng ▁Province , ▁the ▁centre ▁of ▁the ▁gold ▁min ing ▁industry . ▁But ▁there ▁are ▁also ▁important ▁coal ▁mines ▁on ▁the ▁High vel d ▁which ▁are ▁associated ▁with ▁South ▁Africa ' s ▁major ▁electric ity ▁generating ▁power ▁stations . ▁▁ ▁The ▁land ▁is ▁generally ▁flat ▁or ▁g ently ▁und ulating . ▁Only ▁a ▁few ▁rock y ▁rid ges ▁pro tr ude ▁from ▁this ▁flat ness : ▁the ▁V re def ort ▁D ome , ▁the ▁Wit w aters rand ▁R idge ▁and ▁the ▁Mag al ies berg ▁just ▁north ▁of ▁P ret oria , ▁from ▁where ▁the ▁High vel d ▁gives ▁way ▁to ▁the ▁Bush