 DE 261 was originally designated along Foulk Road in the 1930s . In the 1960s , most of the route was widened into a four @-@ lane road . The southern terminus at US 202 was reconstructed into an interchange in the 2000s . PA 261 was first designated in 1928 along Foulk Road between the Delaware border and PA 61 and PA 161 in Chelsea . The route was extended north along Valley Brook Road to US 1 in Chester Heights by 1940 . The northern terminus of PA 261 was moved to its current location by 1980 . 
