717 Area Code
Area code 717 is one of the original 86 area codes created by AT&T and the Bell System in 1947. It originally served the eastern half of Pennsylvania except for the Delaware and Lehigh Valleys. In 1998, area code 570 was created as an overlay to area code 717. To avoid exhausting all possible phone numbers in this area code, relief planning has begun. It is considered, "in jeopardy" which means that it is possible that the supply of numbers could be exhausted before an overlay can be created or the area code splits. Currently, the largest city it serves is Lancaster, PA, and it overlaps coverage areas with area code 223.