Audi has developed the Audi A8 L extended, a built-to-order model measuring 6.36m in length and with a wheelbase of 4.22m to fulfil a special order.

Technicians invested almost a year in developing and building the exceptionally long luxury saloon.

The major challenges concerned the safety and rigidity of the extra-large body, as well as the styling.

The Audi A8 L extended benefits from the low weight of the production model’s body, which uses an Audi Space Frame design and is made almost entirely from aluminium. For the built-to-order version the engineers extended the side sills and centre tunnel using extruded aluminium sections.

Inside the tunnel, these also assist with the air routing. A double rear bulkhead separates the passenger compartment from the luggage compartment; the roof incorporates additional aluminium profiled tubes and cross-braces. These measures provide torsional and flexural rigidity almost on a par with the A8 L.

The representative XXL saloon in discreet moonlight blue, metallic offers 1.09m more wheelbase and overall length than the Audi A8. To maintain a harmonious roof line, the entire body from the A-pillar back has been reworked.

Audi embedded a 2.40-m) glass panel in the roof skin to enhance the sense of spaciousness.

The sun blinds – one for each row of seats – prevent overheating of the interior in strong sunlight. The headlights and rear lights incorporate small side marker lights, as is prescribed by law for vehicles of this length.

All passengers face the direction of travel in the Audi A8 L extended. The six seats are upholstered in extra-supple Valcona leather, in the colour velvet beige. Rows two and three feature electrically adjustable individual seats. The third row has a continuous centre console, a Rear Seat Entertainment display and a cool box.

The one-off A8 version is powered by a 3.0 TFSI engine developing 310hp, delivering up to 440 Nm (324.5 lb-ft) of torque. This propels the saloon from 0 to 62 mph in 7.1 seconds and up to an electronically governed top speed of 155 mph. An eight-speed tiptronic transfers engine power to the quattro permanent all-wheel drive system.

The 19-inch wheels in 15-spoke design conceal the brake system from the Audi S8, to help stop the 2,418kg vehicle.