The calculated distance (air line) between Permatang Kuching and Bukit Mertajam is approximately 9 miles respectively 15 kilometers.
By car or train, the actual journey to Bukit Mertajam is certainly longer, as only the direct route (as the crow flies) between Permatang Kuching and Bukit Mertajam has been calculated here.
Air line (approximately)
15 kilometers
8 nautical miles