Where does Interstate 19 start and end?

Where does Interstate 19

State Of Arizona
Cities Of Nogales, Tucson
Summary actually, Interstate 19 is not a proper Interstate, since it does not leave the state of Arizona at all. It leads from Tucson to Nogales on the Mexican border. On the edge are the Tubac Presidio and the Tumacaori NHP worth seeing. The route is the only interstate in the U.S. awarded in kilometers (currently the Kilometer signs are replaced by miles signs) !
Length 101 Miles
No duty to pay fees

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