Sit on the Left side of the plane for the best views on flights from London to Madrid. While the right side wins at Heathrow departure, the left side delivers the more dramatic sustained views: once the aircraft turns south over England you pick up the English Channel crossing, the Pyrenees appear as a distant wall roughly mid-flight on the left, and the Sierra de Guadarrama arrival view is the visual highlight of the whole route. Left side edges it overall.

During takeoff from Heathrow (LHR), sit on the Right side for the best views. Heathrow typically departs westbound on runways 27L/27R, meaning a right-side seat faces north during the initial climb and turn south. You get a clear view over central London as the aircraft banks left to head south — the Thames, the City skyline, and the sprawl of southwest London are all visible on the right before the turn. Left-side passengers face away from the city toward Windsor and open countryside. Notable sights include: Thames River snaking through southwest London, Windsor Castle and Windsor Great Park to the west, the M25 orbital motorway arc, Wembley Stadium arch visible to the north.

When landing at Barajas (MAD), sit on the Left side for the best views. Madrid Barajas typically lands on runways 32L/32R from the southeast, meaning the approach comes in from the south-southeast. Left-side seats face southwest and get a clear view of the Sierra de Guadarrama mountain range as the aircraft descends — the snow-capped peaks are unmistakable on a clear day. Right-side passengers look east toward flat Castilian meseta with little of interest. Notable sights include: Sierra de Guadarrama range with peaks including Peñalara (2,428m), the Embalse de Santillana reservoir, the urban grid of northern Madrid, the M-30 and M-40 ring roads visible as grey arcs around the city.

The flight from Heathrow (LHR) to Barajas (MAD) takes Approximately 2 hours 15 minutes.

The Bay of Biscay coastline near Bilbao or San Sebastián is visible mid-flight depending on routing — the abrupt transition from green Basque hills to the blue Atlantic is striking. The Pyrenees crossing is the geographic centerpiece of the route, with the main ridge visible as a continuous snow-dusted wall. Over northern Spain the landscape transitions from the green Basque Country to the dry brown Castilian meseta, a dramatic color shift visible clearly from altitude.