The Lehigh Valley ( Pennsylvania Dutch: Lechaa-Daal [ˈlɛçɔd̥ɔːl]), known officially by the United States Census Bureau as the Allentown-Bethlehem-Easton, PA-NJ metropolitan area, is a metropolitan region officially consisting of Carbon, Lehigh and Northampton counties in eastern Pennsylvania and Warren county on the western edge of New Jersey, in the United States. The core population centers are located in southern and central Lehigh and Northampton counties along U.S. Highway 22 and Interstate 78
The Lehigh Valley is the fastest growing and third most populous region in the state of Pennsylvania with a population of 821,623 residents as of the 2010 U.S. Census. It is eclipsed in total population only by the metropolitan areas of Philadelphia and Pittsburgh in Pennsylvania. It is the 64th most populated metropolitan area in the United States. Lehigh County, the Valley's largest county in terms of overall population, is amongst the fastest growing in the nation as well, ranking in the 79th percentile for population growth between 2010-2012. It is part of the New York City metropolitan area.