815 miles
It is 708.04 miles according to MapQuest.
The half way point between Philadelphia, PA and Hilton Head, SC is approximately Rocky Mount, NC. The halfway mileage is 363 miles from Philadelphia, PA. Rocky Mount, NC is 374 miles from Philadelphia, PA.
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The shortest distance is 717 miles.
The shortest driving distance is 694 miles.
It is 700 miles according to Google Maps.
The shortest driving time is 11 hours and 47 minutes.
Google Maps estimates the driving time as 12 hours and 35 minutes.
Erie, PA
305 miles
14 miles
The mileage is about 80 miles, depending what part of Butler and Johnstown you leave and arrive from.