 The northern segment of the highway is maintained by ADOT , who is responsible for maintaining SR 67 like all other highways around the state . As part of this job , ADOT periodically surveys traffic along its routes . These surveys are most often presented in the form of average annual daily traffic , which is the number of vehicles who use the route on any average day during the year . In 2009 , ADOT calculated that around 1 @,@ 100 vehicles used the route daily at its northern terminus in Jacob Lake . The Federal Highway Administration ( FHWA ) lists the highway as a National Scenic Byway , and the National Forest Service has also designated it a National Forest Service Byway . No part of the highway has been listed in the National Highway System , a system of roads in the United States important to the nation 's economy , defense , and mobility . Due to the closure of park facilities on the north rim of the Grand Canyon during winter , winter maintenance is not undertaken after December 1st , with the result that SR 67 is usually closed to vehicular traffic from December 1st until spring . 
 The northern segment of the highway is maintained by ADOT , <a href='null_relcl' title='1'><mark>who</mark></a><a href='drop_aux' title='2'><mark>is</mark></a>responsible for maintaining SR 67 like all other highways around the state . As part of this job , ADOT periodically <a href='uninflect' title='3'><mark>surveys</mark></a> traffic along its routes . These surveys are most often presented in the form of average annual daily traffic , which <a href='drop_aux' title='4'><mark>is</mark></a>the number of vehicles <a href='null_relcl' title='5'><mark>who</mark></a>use the route on any average day during the year . In 2009 , ADOT calculated that around 1 @,@ 100 vehicles used the route daily at its northern terminus in Jacob Lake . The Federal Highway Administration ( FHWA ) <a href='uninflect' title='6'><mark>lists</mark></a> the highway as a National Scenic Byway , and the National Forest Service <a href='been_done' title='7'><mark>has</mark></a> also designated it a National Forest Service Byway . No part of the highway <a href='been_done' title='8'><mark>has</mark></a> been listed in the National Highway System , a system of roads in the United States important to the nation <a href='null_genetive' title='9'><mark>'s</mark></a>economy , defense , and mobility . Due to <a href='None' title='10'><mark>the</mark></a><a href='negative_concord' title='11'><mark>closure</mark></a> of park facilities on the north rim of the Grand Canyon during winter , winter maintenance is not undertaken after December <a href='negative_concord' title='12'><mark>1st</mark></a> , with <a href='None' title='13'><mark>the</mark></a><a href='negative_concord' title='14'><mark>result</mark></a> that SR 67 is usually closed to vehicular traffic from December 1st until spring . 
The northern segment of da highway is maintained by ADOT , responsible for maintaining SR 67 like all other highways around the state . As part of this job , ADOT periodically survey traffic along its routes . dese surveys are most often presented in the form of average annual daily traffic , which tdanumber of vehicles use the route on any average day during the year . In 2009 , ADOT calculated that around 1 @,@ 100 vehicles used the route daily at its northern terminus in Jacob Lake . The Federal Highway Administration ( FHWA ) list thdaighway as a National Scenic Byway , and thedational Forest Service done also designated it a National Forest Service Byway . No part of the highway done been listed in the National Highway System , a system of roads in the United States important to the daion  economy , defense , and mobility . Due to no closure of park facilities on the north rim of the Gdad Canyon durin winter , winter maintenance ain't undertaken after December no 1st , w no result dat SR 67 is usually closed to vehicular traffic from December 1st until spring .