Interstate 579 (I-579) is a north–south Interstate Highway entirely within Pittsburgh, Pennsylvania. The highway is long. I-579 is also known as the Crosstown Boulevard since it crosses the backside of Downtown Pittsburgh. The northern terminus of I-579 is at I-279 beyond the north end of the Veterans Bridge; the southern terminus splits to the Liberty Bridge southbound and Boulevard of the Allies eastbound, which leads to I-376 east. The intersection of I-579 and I-279 is in one direction only; northbound traffic on I-579 can proceed only northbound on I-279 while only southbound traffic on I-279 can exit onto I-579. I-579 allows Liberty Bridge traffic easy access to I-279, and I-279 southbound traffic easier access to PPG Paints Arena, downtown, and eastern regions of the city, while I-279 southbound continues to Acrisure Stadium, PNC Park, and to westbound I-376 which leads to Pittsburgh International Airport. Route description I-579 begins at an interchange with Pennsylvania Route 885 (PA 885; Boulevard of the Allies) and the approach to the Liberty Bridge over the Monongahela River in Downtown Pittsburgh, heading to the north-northeast as a four-lane freeway. At the southern terminus, the highway has a northbound exit and southbound entrance providing access to 6th Avenue and Forbes Avenue near Duquesne University. The road passes several skyscrapers as it comes to an interchange at Centre Avenue with a northbound exit and southbound entrance that provides access to the PPG Paints Arena. Immediately following is a left exit in the northbound direction and a southbound entrance that connects to 7th Avenue that serves the David L. Lawrence Convention Center. At this point, I-579 runs to the west of the former site of the Civic Arena and comes to the PA 380 interchange, a northbound exit and southbound entrance, in addition to a southbound exit and northbound entrance accessing 6th Avenue and 7th Avenue. The freeway turns north as it passes over railroad tracks to the east of Union Station, the Amtrak station serving Pittsburgh. Here, it is seven lanes total with three travel lanes in each direction and two reversible high-occupancy vehicle lanes (HOV lanes) in the center. The HOV lanes connect to Bedford Avenue near the Civic Arena at the south end. The highway turns northwest as it crosses the Allegheny River on the Veterans Bridge. A short distance after the bridge, I-579 ends at an interchange with I-279/US Route 19 Truck (US 19 Truck)