The calculated distance (air line) between Puente de Vallecas and Alcalá de Henares is approximately 17 miles respectively 27 kilometers.
By car or train, the actual journey to Alcalá de Henares is certainly longer, as only the direct route (as the crow flies) between Puente de Vallecas and Alcalá de Henares has been calculated here.
Air line (approximately)
27 kilometers
15 nautical miles