The calculated distance (air line) between Bidur and Bukit Mertajam is approximately 103 miles respectively 166 kilometers.
By car or train, the actual journey to Bukit Mertajam is certainly longer, as only the direct route (as the crow flies) between Bidur and Bukit Mertajam has been calculated here.
Air line (approximately)
166 kilometers
89 nautical miles