Sit on the Left side of the plane for the best views on flights from Seattle to London. Left side wins at both ends of the flight. During takeoff you get Lake Washington and the Cascades including Rainier, and on arrival into Heathrow you get Windsor Castle, the Thames, and the London skyline. The right seat offers comparatively little at either end.

During takeoff from Boeing Fld King Co International (BFI), sit on the Left side for the best views. BFI's primary departure runway is 13R, heading southeast, then aircraft typically turn northbound for transatlantic routing. On a left (east) seat during initial climb and northward turn, you get a direct view of Lake Washington and the Cascade Range. Mount Rainier dominates the southeast horizon at around 14,000 feet elevation and is unmistakable from the air. Notable sights include: Lake Washington directly below, Mount Rainier to the southeast, the Cascade Range stretching north-south, Elliott Bay and downtown Seattle briefly visible to the west during the turn.

When landing at Heathrow (LHR), sit on the Left side for the best views. Heathrow's most common arrival is from the west on runway 27L or 27R, meaning the aircraft approaches heading east. A left (south-facing) seat on final approach gives you views over Windsor Castle, the Thames bending through west London, and the dense urban fabric of southwest London. The right seat faces north toward less distinctive suburban terrain. Notable sights include: Windsor Castle and Windsor Great Park, the River Thames curving through Richmond and Twickenham, the urban sprawl of southwest London, Wembley Stadium visible to the north if on 27L approach.

The flight from Boeing Fld King Co International (BFI) to Heathrow (LHR) takes Approximately 9 to 10 hours nonstop.

The great circle route from Seattle to London tracks northeast over British Columbia and Alberta, crossing the Canadian Rockies visible from both sides in good weather, then over Hudson Bay or northern Quebec depending on winds, across the Labrador Sea, southern Greenland's ice sheet and fjord coastline, then Iceland or the Faroe Islands, before descending across Scotland and northern England into London. The Greenland ice cap and Icelandic volcanic terrain are the most visually dramatic midpoint features.