"It seems to me that carved tracks were not unique to Malta."
Your example is a bit different because Greeks and romans built and used robust paved roads designed to sustain heavy and frequent passages. But anyway, this pavement shows clear wearing traces, so what?
Hereunder are examples on two linked questions:
1-Were the widths of carts and roads standardized accordingly
Your photo answers "yes".
2-Were there, in cases of difficult passage, traces of man-dug ruts to guide wheels in order to prevent slipping sideways?
Here again the answer seems to be yes.
So both answers to wheels traces on pavements are true: Many are worn by repeated passages of cart wheels with standard gauge, and there were cases when some difficult passages imposed to carve ruts to guide wheels.
In addition, there is a debate as to know if roman gauge standardization led to modern industrial railway gauge through the long story of medieval and pre-industrial transportation activities. It is another story.
subject="Ancient roads of the Romans, not readable graphics on site but useful informations"
Edited 1 time(s). Last edit at 30-Nov-17 11:01 by Mike D.