These are a fascinating part of the desert landscape. As you travel they change according to the colour of the soil and the species of termite. They were a deep red here and shoulder high where in other places they can be shorter, taller, nearly black or pale grey. In some areas there are so many they look like a city. Further North some species orient their structures according to North/South poles to control heat inside.
@randystreat no you don't see termites unless you break into the structure, which I wouldn't do as they would have to mend it. They are not huge, some are quite tiny!
Ian