 By 1920 , what is now DE 261 existed as a county road . When Delaware first assigned state highway numbers by 1936 , what is now DE 261 had been upgraded to a state highway , but did not receive a number at that time . By 1938 , DE 261 was designated onto its current alignment between US 202 and the Pennsylvania border , continuing the PA 261 designation . DE 261 was widened into a four @-@ lane road between US 202 and Silverside Road by 1966 . The four @-@ lane portion was extended north to <unk> Road a year later . In summer 2007 , construction on converting the intersection with US 202 into interchange was completed as part of the Blue Ball Properties project , a project undertaken to improve roads in this area as part of <unk> locating their North American headquarters to the area . DE 141 was also realigned to intersect US 202 and DE 261 at this interchange . The total cost of the project was $ 123 million . 
