Visiting Cape Town a collector can visit 2 sites. First is Robben island and second is Cape Floral Region.
This site consists of six (?) parts which are geographicaly in whole region of Western Cape.
So I visited only the "Kirstenbosch Botanical Garden" and Cape Point National park. The whole region is a housing of Fynbos ("fine bush") which is rare only for this part of world. The natural location is very nice and I enjoyed my stay there, especialy on Cape Point even it is very windy. Just be prepared that you will need a whole day for such a trip.
Pic: Lighthouse on Cape Point surrounded by Fynbos