Security measures implemented following the September 11 attacks prohibited commercial truck traffic from driving across Hoover Dam . Prior to the completion of the bridge , through commercial vehicles were required to follow a detour of between Boulder City and Kingman via US 95 , Nevada State Route 163 , the Colorado River crossing between Laughlin , Nevada and Bullhead City , Arizona , and Arizona State Route 68 ; although the detour was long , it only added to the normal journey on US 93
September 11 attacks
September 11 attacks
Mike O'Callaghan–Pat Tillman Memorial Bridge