
Nicknamed the Keystone State for the pivotal role it played in colonial days, Pennsylvania has transformed itself from an industrial hub whose strength rested on coal mining and steel production to a state with a diversified economy that includes natural gas, manufacturing, agribusiness,...

Nicknamed the Keystone State for the pivotal role it played in colonial days, Pennsylvania has transformed itself from an industrial hub whose strength rested on coal mining and steel production to a state with a diversified economy that includes natural gas, manufacturing, agribusiness,...
