The ribbon of light is the Grand Trunk Road which runs from Afghanistan
to Bangladesh. It was built in the 3rd Century BC, which was about the last
time they repaired the potholes in it as well.
Gary I know a part of that route well, having gone from India,through Pakistan, Afghanistan,then veered off through Iran to Turkey.
I can vouch for the condition of the road, well at least in 1977.
Cheers