Lee from Fort Collins writes, “What’s driving you crazy? Hi Jayson, can you tell us what this marking is for? There is one on the shoulder of Hwy 14 and Weld County Road 19 between Ft Collins and Ault.”
This is the mark Lee is talking about.
It is a square with two black and two white squares making up a larger square. Since it is on Colorado Highway 14 east of Interstate 25, I brought Lee’s question to Jared Fiel with Colorado Department of Transportation . He told me, these types of markings are used for aerial imagery or aerial drone surveys.
According to the website pix4d.com , these markings are better described as ground control points. They act as a reference point that the drone or other aircraft uses to know where they started and where they will come back to. These control points can be any shape or color that is easily recognized from the air but are almost always black and white squares because it’s easier to recognize high contrast patterns.