I have just returned from a weekend hiking in the Drakensberg where I encountered Disa crassicornis growing at the foot of large sandstone cliffs. Many other terrestrial orchids can be seen in similar habitats, e.g. Disa fragrans, Huttonea grandiflora, Satyrium parviflorum, Disperus faninnae, etc.
Arguably, D. crassicornis is the most beautiful of all: