The calculated distance (air line) between Merthyr Tydfil and Pontypridd is approximately 10 miles respectively 16 kilometers.
By car or train, the actual journey to Pontypridd is certainly longer, as only the direct route (as the crow flies) between Merthyr Tydfil and Pontypridd has been calculated here.
Air line (approximately)
16 kilometers
9 nautical miles