The calculated distance (air line) between Concepción Tutuapa and Retalhuleu is approximately 50 miles respectively 80 kilometers.
By car or train, the actual journey to Retalhuleu is certainly longer, as only the direct route (as the crow flies) between Concepción Tutuapa and Retalhuleu has been calculated here.
Air line (approximately)
80 kilometers
43 nautical miles