Interstate 579

Interstate 579 (abbreviated I-579) is a north–south Interstate Highway entirely within Pittsburgh, Pennsylvania. At 1.57 mi (2.53 km) long, it is short but not the shortest signed Interstate, an honor which belongs to I-375 in Michigan. 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 Interstate 279 on the Veterans Bridge and the Interstate 279 Interchange, while the southern terminus splits into the Liberty Bridge and Boulevard of the Allies, which connects to eastbound Interstate 376. 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 Consol Energy Center, downtown, and eastern regions of the city, while I-279 southbound continues to Heinz Field, PNC Park, and to westbound I-376 which leads to the Pittsburgh International Airport.

Construction on Interstate 579 was not completed until 1989, with the opening of the Veterans Bridge, and the opening of Interstate 579 was concurrent with the opening of an extension of Interstate 279 into the North Hills region of the Pittsburgh metropolitan area.

In the past, this was first Interstate 876 and then Interstate 479 prior to becoming Interstate 579. The change from 876 to 479 was because it didn't connect to I-376 (then I-76), and then it was changed to 579 because it only connected to an interstate at one end.