A rare piece of car history is headed to the auction block. Named after the King of Spain who reigned from 1886 until 1931, the Type Alfonso XIII is set to go on sale at an upcoming Amelia Island auction, and is expected to fetch somewhere between US$750,000 and $1 million.

King Alfonso XIII of Spain was a huge fan of the luxury vehicles of Spanish automotive firm Hispano Suiza, and owned close to 30 cars made by the company which he kept stored throughout Europe. Hispano Suiza originally planned on naming the 1911 vehicle up for auction the 15T, but decided to instead name it after the king at the time. It's one of the rarest cars in the world - only four were ever made.

The Alfonzo is considered one of the first real sports cars. The vehicle came packing a Birkigt-designed massive cast-iron Type 15T four-cylinder engine, and is capable to producing 64 horsepower with only 3.6 liters of displacement. The car was the high-end of what car manufacturers were producing in the day, and was capable of a top speed of over 75 mph (120 km/h), super-fast for the early 1900s.

From the car's listing at RM Auctions:

There is no shortage of charming details to behold on this car. Among them are the original Bleriot two-bulb headlamps, possibly an early hi-beam/low-beam setup, with Ducellier cowl lamps, a large roof rack and a fold-out windshield. The original interior is amazingly preserved for being almost a century old, while the fabric is so intricately woven that it could be compared more to the celebrated Flemish tapestries than automobile upholstery. Where the headliner has come away from the ceiling can be observed a series of small thin squares of wood, which would have given texture to the ceiling with the headliner attached. The dash is very nicely finished as well and still contains all of its original instruments.

The styling and curves of this gorgeous baroque winter body is amazing, with two separate compound curves making up the roof sections, which almost resemble ceiling vaults. The wood-framed windows are of such proportion that they appear to have come out of a home. When a car is restored to concours specifications, the high standards demanded today require complete recreation of otherwise serviceable parts. What is lost are fine details and markings that give an automobile character and authenticity.

Among the myriad items found on chassis 718 are the markings on the trunk hardware and leaf springs, the original dash chassis plate and the plate that reads Radiadores Vintro Barcelona on the upper radiator tank. There are other pieces like the intricate brass locks on the original Hispano-Suiza center caps complemented by the nicely aged black wire spoke wheels.

Chassis 718 is a perfect example of sympathetic preservation. Any early example of the Hispano-Suiza marque is something special that should garner extra attention, but as a special long-wheelbase example of the revered Alfonso XIII, it is likely that there are no other direct comparisons to be had.

Like the casks of wine which surrounded it for so much of its life, this Hispano-Suiza Alfonso XIII Double Berline has gotten better with age. It is, truly, one of the greatest antiques in existence.

The 1911 Hispano-Suiza King Alfonso XIII is set to be auctioned off on March 10, 2012.

For more details check out the car's official auction page at RM Auctions.

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