High Quality Content by WIKIPEDIA articles! Route 15 is a state highway in Morris and Sussex County, New Jersey. The route heads for 19.16 miles (30.84 km) from East McFarland Street (U.S. Route 46) in Dover to an intersection with U.S. Route 206 in Frankford Township. The route becomes a divided highway in Jefferson Township until becoming a freeway bypass near Sparta. Route 15 was originally Route 6A from 1927 until 1953, when a renumbering occurred. The route was eventually bypassed around the community of Sparta which became New Jersey Route 181.