The calculated distance (air line) between Pirdop and Gorna Oryahovitsa is approximately 82 miles respectively 132 kilometers.
By car or train, the actual journey to Gorna Oryahovitsa is certainly longer, as only the direct route (as the crow flies) between Pirdop and Gorna Oryahovitsa has been calculated here.
Air line (approximately)
132 kilometers
71 nautical miles