The calculated distance (air line) between Băile Herculane and Ploieşti is approximately 176 miles respectively 284 kilometers.
By car or train, the actual journey to Ploieşti is certainly longer, as only the direct route (as the crow flies) between Băile Herculane and Ploieşti has been calculated here.
Air line (approximately)
284 kilometers
153 nautical miles