The calculated distance (air line) between Villa de Vallecas and San Martín de la Vega is approximately 11 miles respectively 18 kilometers.
By car or train, the actual journey to San Martín de la Vega is certainly longer, as only the direct route (as the crow flies) between Villa de Vallecas and San Martín de la Vega has been calculated here.
Air line (approximately)
18 kilometers
10 nautical miles