"North" . "South" . . . "54074.0"^^ . . . . . . "Pennsylvania Route 551 (PA 551) is a 34-mile-long (55 km) state highway located in Beaver, Lawrence, and Mercer Counties in Pennsylvania. The southern terminus is at PA 18 in Beaver Falls. The northern terminus is at PA 18 near West Middlesex.Though officially a spur route of Pennsylvania Route 51, PA 551 is more suited as a spur route of PA 18, due to PA 551 ending at PA 18 at both ends without intersecting with PA 51 at all."@en . "551" . . . . . "PA" . . .