The N-420 is a highway in Spain.
The road starts 36 km east of Córdoba at Montoro. The N-420 runs north through the heavily wooded Sierra Morena passing over the Puerto de Niella then crossing the valley of the Rio Montoro before taking the Puerto Pulido to Puertollano. The AVE Sevilla-Madrid runs parallel to the road on its way to Ciudad Real.
Thereafter the road follows the Autovía A-43 before branching north to cross the A-4 again at Puerto Lapice, south of the Montes de Toledo. 21 km to the east the road passes Alcázar de San Juan and the Autovía CM-42 which is an upgrade of the CM-400. The landscape here is dominated by hill top Windmills.
Coordinates 41°0'0.693" N 0°7'16.144" E