US 93 has an interchange with SR 68 (exit 67). This junction incorporates a large Commercial Vehicle Inspection Station (CVIS), which ADOT calls a "Port of Entry" (POE), for southbound and eastbound commercial traffic. Highway 68 heads west over the Black Mountains to Davis Dam, Laughlin, and Bullhead City (the latter via SR 95), while US 93 continues as a four-lane divided route towards the northwest. Running through the long Detrital Valley, with the Black Mountains to the west and the Cerbat Mountains and then the White Hills to the east, US 93 passes several small settlements in this most remote area. As it nears the Nevada state line, it enters the Lake Mead National Recreation Area and climbs over Householder Pass, before crossing into Nevada via the Mike O'Callaghan–Pat Tillman Memorial Bridge over the Black Canyon just downstream of the Colorado River from Hoover Dam. US 93 continues into Nevada to the cities of Boulder City, Henderson and Las Vegas as part of Interstate 11 (I-11). History The route between Kingman and Hoover Dam first became part of the state highway system in 1934 when it was designated as SR 69. At the time, Hoover Dam was still under construction and the highway did not link to Nevada. The dam was completed the following year in 1935 enabling traffic to cross over the top of the dam. In that year, US 466 was designated over SR 69 from Kingman to Hoover Dam. US 93 was extended south from (then) US 91 at Glendale, Nevada later the same year. In 1935, Arizona proposed an extension of US 93 from Kingman to Ash Fork, overlapping US 66, and then south to Phoenix. This proposal was protested by the towns of Aguila and Wickenburg that argued that US 93 should pass through their towns rather than the proposed alignment to the east. The town of Wickenburg contested that a direct routing between Phoenix and Kingman would be shorter than the routing through Ash Fork and that it would provide a necessary connection between Phoenix, the state capital and the northwestern part of the state. Until 1937, the originally proposed extension overlapping US 66 stayed in planning as US 93T. Another route, US 193, was also planned, traveling from Phoenix through Sacaton and Casa Grande before terminating in Picacho. US 193 was briefly reworked under the designation US 93A before the proposal was