County Line Road (Adams-Weld)

Baseline Road is a major east-west street in Boulder, Colorado that extends east of the city through parts of four counties. The western terminus of Baseline Road is at Flagstaff Mountain in the City of Boulder Mountain Parks. The eastern terminus is at 16800 Watkins Road, about 6 miles (9.7 km) east of Lochbuie on the boundary between Adams and Weld Counties. The total length of Baseline Road is approximately 38 miles (61 km), all of which is within the Denver-Aurora-Boulder Combined Statistical Area in Colorado. Baseline Road runs almost exactly along the 40th line of latitude.

On May 30, 1854, the Kansas-Nebraska Act created the Kansas Territory and the Nebraska Territory, divided by the 40th parallel north. The Pike's Peak Gold Rush of 1858-1861 lured thousands of gold seekers into the goldfields of the northwestern Kansas Territory and the southwestern Nebraska Territory. On February 28, 1861, the western portion of the Kansas Territory and the southwestern portion of the Nebraska Territory were incorporated into the new Colorado Territory. The 40th parallel became the primary baseline for surveying the land in the eastern portion of the new territory, and a road was eventually cut along the survey baseline.

The road along the 40th parallel is officially named Baseline Road in Boulder County and the City and County of Broomfield, 168th Avenue in Adams County, and County Line Road or Weld County Road 2 in Weld County.

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Wikipedia