When the US Interstate Highway system was being designed and
constructed in the 1960s, a feature of the design was that at least
one in every five miles of roadway would be straight and suitable for
use by military aircraft in the case of extreme unpleasantness with
the Soviets.

I had heard that, and I believe I had also seen that this is not the case.
I could not find anything one way or the other.

Do you happen to know of a citation from some authority that says what you
stated?

I have heard the myth also, but read the following.


http://geography.about.com/gi/dynami...mileinfive.htm

ONE MILE IN FIVE: Debunking the Myth

by Richard F. Weingroff