Harrisburg is located on the eastern bank of the Susquehanna River, 100 miles west of Philadelphia, at a gap in the Blue Mountains between the Cumberland and Lebanon valleys created by the river. The terrain is rolling, with a band of flat land in the southern part of Dauphin County ranging up to a mile wide along the Susquehanna River. The region is underlain by limestone which, combined with the gently rolling terrain, creates an ideal farming environment.
Harrisburg's climate is humid continental; there are four distinct but mild seasons. Summers are warm to occasionally hot with relatively high humidity; winters are comparatively mild for the region's latitude.
Area: 11.44 square miles (2000)
Elevation: Ranges from 100 to 358 feet above sea level
Average Temperatures: January, 28.6° F; July, 73.5° F; average annual temperature, 52.9° F
Average Annual Precipitation: 40.5 inches of rain; 34.3 inches of snow