US 93, Route 93 or sometimes U.S 93, is a highway in eastern Nevada and western Arizona. It begins in Kingman and ends in the town of Jackpot, A small border town between Nevada and Idaho. Along the way you go past Ely, Pioche, Las Vegas and finally Kingman (Presuming you began in Jackpot). US 93 is an essential highway because of its connects the north of Nevada to Las Vegas aswell as southern California. US 93 is believed to be continued when an Idaho DLC is added to American Truck Simulator. No information has been given at this time.
An amusing easter egg can be found at a Rest Stop between Las Vegas and Pioche. If you are to pull up at this Rest Stop and look at the nearby army base, You will see two rubber duckies bobing up and down behind the fence. This is better explained here - Easter Eggs in American Truck Simulator.