The calculated distance (air line) between San Diego de la Unión and Santiago de Querétaro is approximately 68 miles respectively 110 kilometers.
By car or train, the actual journey to Santiago de Querétaro is certainly longer, as only the direct route (as the crow flies) between San Diego de la Unión and Santiago de Querétaro has been calculated here.
Air line (approximately)
110 kilometers
59 nautical miles