The calculated distance (air line) between Águas Santas and Viana do Castelo is approximately 36 miles respectively 58 kilometers.
By car or train, the actual journey to Viana do Castelo is certainly longer, as only the direct route (as the crow flies) between Águas Santas and Viana do Castelo has been calculated here.
Air line (approximately)
58 kilometers
31 nautical miles