These trees are on the slopes of Signal Hill. What may not be immediately obvious is that the area directly behind these trees has been stripped clean of most vegetation, creating a firebreak to slow the progress of the fires that break out on the hills and mountains in this area each year.
What you may find strange is that, to survive, the fynbos flora that covers our mountains and hills actually needs to burn, preferably in late summer, every 10 to 15 years. Strange hey? Read a little more about this on the Encounter South Africa site.