If you're looking for a meeting place or a good stop around ½ or halfway between Erie and Robinson, PA, you can try North Mills, PA, which is almost an hour south of Erie, or about 1 hour north of Robinson, PA.
Other possible places to stop near the midpoint include Nesbit Corners, Filer Corners, Irishtown, and Blacktown.
About ¼ or a fourth of the way, you can stop at Meadville, PA. This is about half an hour south of Erie.
About ⅓ or a third of the way, you can stop at Custards, PA. This is almost an hour south of Erie.
About ⅔ or two thirds of the way, you can stop at Heath, PA. This is a little over 1 hour south of Erie, or almost an hour north of Robinson, PA.
About ¾ or three fourths of the way, you can stop at Middle Lancaster, PA. This is about 1½ hours south of Erie, or about half an hour north of Robinson, PA.
If you drive straight through without stopping at all, the total distance is 128 miles. The distances shown above don't include local roads to get into each town, so if you're planning a long road trip, make sure you factor in traffic and road conditions, rest stop breaks, and interesting detours along the way. If you're in a rush, you can do the trip with zero stops, and your total travel time would be around 1 hour, 60 minutes.