A news blurb last week from the Wheeling News Register highlights how hard the question is here. The story mentions the impact of people moving towards them from Pittsburgh. They have a quote mentioning how it's actually a shorter commute from Wheeling into Pittsburgh than from many communities in the Pittsburgh region. That is true, yet we rarely talk about Weirton or Weirton as being part of the Pittsburgh Region. It is not part of the seven county Pittsburgh Metropolitan Statistical Area(MSA), nor is it part of the 10 county Southwestern Pennsylvania region that is often used as a benchmark.
I am by far not the first person to ask what defines the Pittsburgh region? The Bureau of Economic Analysis has for some time defined the Pittsburgh Economic area as 19 counties. Some know that John Craig, former editor of the Post-Gazette, focuses on this question. His vision is a Pittsburgh region defined as 22 counties and stretching into both Ohio and West Virginia. (that requires an obligatory plug for the PittsburghToday project that is attempting to operationalize that definition.)
Are their further connection even further afield? I will not even begin to address the Pittsburgh Manifesto/Diaspora concept that thinks of a virtual Pittsburgh everywhere. How about Pittsburgh's connection to Washington, DC? That may be far away, but I am pretty sure there are already at least some impacts of Washington, DC regional growth beginning to push up against the southwestern edges of the Pittsburgh region. The Pittsburgh-DC connection may sound far fetched but I actually thought of this post by noticing in the logs for this site that someone actually found this recent post via a google search "commuting between Pittsburgh and DC". Less talked about, but the interconnections with Cleveland (aka Cleveburgh) are already real enough.
Likewise, connections into West Virgina, including the Weirton/Wheeling/Steubenville areas, but also into Morgantown, which is one of the faster growing areas near Pittsburgh. If you take an even bigger view, it has come into vogue again to talk about the broad Great Lakes region, although some have realized it's importance for some time.
Other definitions of the region: Nature does not feel obliged to respect artificial political boundaries, and the Pittsburgh region's watershed has its own ideas of what defines the region. Finally, something that has always puzzled me. Why do we never mention Canada, in particular our immediate neighbor Ontario to the north, when discussing these types of broad regional issues? A different country for sure, but it is only a few hours north of here. If there is no other connection, I know more than a few Pittsburghers who have gone to college in Canada. But Canada is also one of the largest trading partners with Pennsylvania. It seems like we should pay attention a little more to the Great White North. We once did. Not long ago Pittsburgher Adolph Schmidt was actually the ambassador to Canada.
Even if we come up with a definition, it will not be a static definition. Even the most commonly used Pittsburgh MSA definition is not static. Currently the MSA is made up of seven counties, but has been fewer counties in the past and will likely soon be refined to include Indiana County as number 8.
So my answer is of course a non-answer. There is no one definition that meets all needs, but we need to talk more about what the different versions of the region could be if we ever want to move from vague generalities to practical decisionmaking.