The calculated distance (air line) between Grahamstown and Graaff-Reinet is approximately 137 miles respectively 221 kilometers.
By car or train, the actual journey to Graaff-Reinet is certainly longer, as only the direct route (as the crow flies) between Grahamstown and Graaff-Reinet has been calculated here.
Air line (approximately)
221 kilometers
119 nautical miles