That’s because I-19 is the only American highway that fully measures distance in kilometers, a relic of a failed effort in the 1970s for the U.S. to adopt the metric system. Some 50 years later ...

The Carter Administration did get one interstate highway to adopt the metric system. The 63-mile long I-19 in Southern Arizona became a 102-kilometer long interstate. ADOT ...

The bodies of nine students who went missing on vacation in southern Mexico last month have been found dismembered by the side of a local highway — with a bag of hands nearby.

I-19, which connects Tucson and Mexico, has measured distance in kilometers since the 1970s. It’s now under review I-19, which connects Tucson and Mexico, has run on the metric system since the ...