I've been looking for a heightmap of South Africa for a while but I can't seem to find the kind I need anywhere. It needs to be a Grayscale Raster of high quality.
OpenTopography supports downloading heightmaps (and other data) from several sources.
Here's the current sources available for South Africa:
1 Copernicus Global Digital Elevation Models
2 NASADEM Global Digital Elevation Model
3 Global Bathymetry and Topography at 15 Arc Sec: SRTM15+ V2.1
4 Global Multi-Resolution Topography (GMRT) Data Synthesis
5 ALOS World 3D - 30m
6 Shuttle Radar Topography Mission (SRTM) Global
You may need some dataprocessing to convert the raw data to Grayscale Raster.