The region is composed of six counties in south-central Pennsylvania, and within the Mid-Atlantic area of the United States. The counties comprising the region include Fulton, Huntingdon, Blair, Bedford, Somerset and Cambria. The majority of the region is rural and forested.  The total land area is 3,400 square miles. The one geographic factor linking all counties in the region is the Allegheny Mountain Range of the Appalachian Mountains, with some mountain ridges in each of the six counties.

The geography of the region includes a mix of low, rugged, mountain ranges, rolling countryside, and river valleys.  A number of rivers and creeks run through the region, with the best known being the Juniata River. The largest inbound lake in Pennsylvania, Raystown Lake, a 30 mile lake with 118 miles of shoreline, is located in the region.

The climate of the region is known as humid continental, but has some characteristics of a mountain type climate.  It is relatively cool at higher spots in the region, with snow in the winter and relatively cool summers. 

The history of the region is linked to coal, steel, railroads, and agriculture.  The region had numerous mines and huge steel mills during peak periods in those industries.  The coal and steel industry in the region declined sharply in the 1980s, with only limited activity in these industries remaining. 

The economy of the Southern Alleghenies Region is now more diverse than it was a decade ago, with no reliance on any one sector. Nearly two-thirds of the jobs in the region are concentrated in five sectors: health care and social assistance, retail trade, manufacturing, accommodations and food service and other professional services. 

There are two cities in the region with a population of over 20,000 – Johnstown in Cambria County and Altoona in Blair County.  At the time of the 2010 Census, Altoona had a population of 46,320, Johnstown had a population of 20,978, and their combined population of 67,298 represented 15% of the regional population of 459,030.

The Southern Alleghenies Region has a robust transportation network including (North/South) U. S. Routes I-99 and 219, which connect the region to Interstate 80 and (East/West) the PA Turnpike, and U.S. Route 22. Interstate 70 connects the Washington/ Baltimore and southern markets to the region in Breezewood. The region also has a fully developed rail system with both short line spurs and mainline connections.

In general, the Southern Alleghenies Region is a relatively rural region, close to the large Pittsburgh area on the west and not far from the State Capital in Harrisburg on the east.  The outer areas of the Washington metro area are only a one-hour drive from parts of the southern end of the Southern Alleghenies Region.