Interstate 376 (I-376) is a major auxiliary route of the Interstate Highway System in the US state of Pennsylvania, located within the Allegheny Plateau. It runs from I-80 near Sharon south and east to a junction with the Pennsylvania Turnpike (I-76, its parent) in Monroeville, after having crossed the Pennsylvania Turnpike at an interchange in Big Beaver. The route serves Pittsburgh and its surrounding areas and is the main access road to Pittsburgh International Airport (PIT). Portions of the route are known as the Beaver Valley Expressway, Southern Expressway, and Airport Parkway. Within Allegheny County, the route runs along the majority of the Penn-Lincoln Parkway, known locally as Parkway West and Parkway East. It is currently the ninth-longest auxiliary Interstate route in the system and second only to I-476 within Pennsylvania. I-376 is signed east–west despite running north–south for nearly three-quarters of its length; however, it does run east–west through the majority of Allegheny County. This is because, until 2009, the route's western terminus was at I-279 in Downtown Pittsburgh; it was extended west and north to I-80 to give the corridor a single route designation. Despite the route's direction, it serves as a major artery through Pittsburgh's West End, with I-79 being the primary route through Pittsburgh's North Hills. Since its 2009 extension, the route has also served as a major way to access Northeast Ohio. A stretch of the Beaver Valley Expressway, officially named the James E. Ross Highway, from exit 15 where I-376 ends its brief concurrency with U.S. Route 422 (US 422) to exit 31 where I-376 has its first interchange with Pennsylvania Route 51 (PA 51), is tolled and is maintained by the Pennsylvania Turnpike Commission (PTC), while the remainder of the highway is maintained by the Pennsylvania Department of Transportation (PennDOT). Near the airport, I-376 also has a business loop. Route description Beaver Valley Expressway and Airport Parkway I-376 begins at a cloverleaf interchange with I-80 and PA 760 located east of Ohio within the Glaciated Allegheny Plateau. From there, it travels in a southerly direction on the Beaver Valley Expressway, a four-lane freeway with a wide grass median. Paralleling PA 18, I-376 has its first interchange with that state highway in West Middlesex. I-376 soon meets US 422 and forms an overlap with that highway along the west side of New Castle. After an interchange with US 224 in Union Township, I-376 eastbound