Pennsylvania border, where Limestone Road continues north into that state as SR 3013, an unsigned quadrant route that heads to an interchange with PA 41. The section of DE 7 between Old Baltimore Pike in Christiana and DE 4 in Stanton is part of the Washington–Rochambeau Revolutionary Route, a National Historic Trail. DE 7 has an annual average daily traffic count ranging from a high of 95,797 vehicles at the south end of the DE 4 concurrency to a low of 3,294 vehicles at the Old Baltimore Pike intersection. The portion of DE 7 from the south end of the DE 1 concurrency to the Pennsylvania border is part of the National Highway System. History What would become DE 7 originally existed as a county road by 1920. By 1924, the road was paved between Christiana and Stanton and was upgraded to a state highway between Capitol Trail and New Linden Hill Road. A year later, the road was upgraded to a state highway between Bear and Christiana and between Paper Mill Road and Brackenville Road, with all the sections south of Bear, between New Linden Hill Road and Paper Mill Road and Brackenville Road and the Pennsylvania border proposed as a state highway. By 1931, these sections of state highway had been completed. DE 7 was designated to run from US 13 south of Red Lion north to the Pennsylvania border by 1936, following its present alignment. In 1937, the narrow swing bridge over the Christina River in Christiana was replaced with a stone bridge. A concrete tied-arch bridge was built over the White Clay Creek in Stanton in 1941. By 1959, DE 7 was widened into a divided highway between Stanton and DE 2. The divided highway was extended north to Milltown Road by 1966. By 1985, DE 273 was realigned to bypass Christiana, removing it from a portion of DE 7 through the town. Also at this time, the route was widened into a divided highway from the Christiana Mall north to Stanton. The route was shifted west to a new alignment passing over the Amtrak tracks and the White Clay Creek. In the 1980s, a freeway relief route for DE 7 was proposed to run between US 13 in Tybouts Corner and I-95 in Christiana in order to reduce congestion along DE 7. In 1988, this relief route became part of DE 1, a freeway connecting