think they know how to read the numbers, but they
may understand only part of the story. Other motorists
are confused by the numbers; still others have
never really thought about it.
numbered interstates (1 to 2 digits) are east-west
routes. They go from I-10 in the south to
I-94 in the north.
numbered interstates (1 to 2 digits) are north-south
routes. They start with I-5 on the West Coast
to I-95 on the East Coast.
numbered interstate highways connect major highways.
If the first digit is an odd number this usually
a "spur" route heading from an interstate
to a destination, such as a city center.
An even number means the highway connects to
a interstate at both ends (typically a "beltway"