Of 67 counties in the Keystone State, Armstrong County ranks 34th by size (663 square miles). Armstrong County is in Pittsburgh & Countryside Pennsylvania. Armstrong County, Pennsylvania, includes about 1,000 acres of riverfront property for sale based on recent Land Network data. The combined market value of farms, rural land, hunting land and other land for sale here was nearly $900,000. Browse all waterfront property for sale in Armstrong County on the Land Network to find the marina, lakefront and other recreational property that meets your needs, from waterside land perfect as a retirement investment to existing residential waterfront land and property for hunting, fishing and other outdoor-recreation pursuits! The most common type of land for sale by combined acreage in Armstrong County is residential property.