The calculated distance (air line) between Chamartín and San Sebastián de los Reyes is approximately 7 miles respectively 11 kilometers.
By car or train, the actual journey to San Sebastián de los Reyes is certainly longer, as only the direct route (as the crow flies) between Chamartín and San Sebastián de los Reyes has been calculated here.
Air line (approximately)
11 kilometers
6 nautical miles