It is in Lancaster this year. Here is the call for papers as posted at New York History blog:
The Pennsylvania Historical Association have announced they are now accepting proposals for its 2018 annual meeting to be held in Lancaster, PA from October 11-13.
The program committee welcomes and encourages proposals on all aspects of Pennsylvania and Mid-Atlantic history.
The conference theme is “City, County, Commonwealth, and Country: Local and Regional History as America’s History,” with proposals especially encouraged in the areas of material culture, public history, and oral history. Full session proposals are strongly preferred, but the committee will also consider individual paper proposals. Sessions may be arranged as either paper panels or roundtable discussions. The program committee also invites proposals for our student research poster session.
If you have suggestions for panel or plenary sessions related to the conference theme, contact the program chair, Dr. Michael Birkner (Gettysburg College) at firstname.lastname@example.org. The annual meeting is hosted by LancasterHistory.org.
Proposals must be submitted electronically by March 10, 2018.