Interstate 79

Interstate 79 is an Interstate Highway in the United States. It goes from Charleston, West Virginia north to Erie, Pennsylvania. The route is  long. It is a primary thoroughfare through western Pennsylvania and West Virginia. It is also an important corridor to Buffalo, New York, and the Canadian border. From Sutton north, Interstate 79 generally parallels the path of U.S. Route 19.  With the exception of the area between Washington and Cranberry Township, Pennsylvania, I-79 functionally replaces U.S. Route 19.

In West Virginia, Interstate 79 is called the Jennings Randolph Expressway. In the three most northern counties it is part of the "High Tech Corridor". Through most of Pennsylvania, it is called the Raymond P. Shafer Highway.
Auxiliary routes
Interstate 279 heads southeast from Interstate 79 in Pittsburgh's northern suburbs to Interstate 376 in downtown Pittsburgh.
Interstate 579 heads south from Interstate 279 in Pittsburgh's North Side to the Liberty Bridge and the Boulevard of the Allies just east of downtown Pittsburgh.

References

79