Northampton County, PA's area is 377 square miles.
142.6 square miles check out wikipedia the answer is right there.
If you are sking how many square miles are in Pennsylvania then the answer is 46,055 square miles. The state is ranked 33rd in area in the country.
44,817 square miles
Pittsburgh, PA is 58.3 sq miles (151 km²).
46,058 square miles (ranked 33rd).
Not sure what is was and when, but it is approx 44825 square miles.
Erie County - 1,558 square miles.