The Arrowhead Trail or Arrowhead Highway was the first all-weather road connecting Los Angeles to Salt Lake City by way of Las Vegas. Built primarily during the auto trails period of the 1910s, prior to the establishment of the U.S. numbered highway system, the road was replaced in 1926 by U.S. Route 91 and subsequently Interstate 15. Small portions of the route in California and Las Vegas, Las Vegas Boulevard, are sometimes still referred to by the name, or as Arrow Highway.