A steam-powered car, considered the oldest vehicle in the world still running, has sold at auction in the United States for more than $4.6 million.

The De Dion-Bouton et Trepardoux Dos-a-Dos Steam Runabout, nicknamed La Marquise, which was built in France in 1884, sold for more than twice its estimate at auction Friday in Hershey, Pennsylvania.

RM Auctions listed its top speed as 61 kilometres per hour and said it had only had four owners over the past 127 years.

Late Texan collector John O'Quinn had bought the historic car, which participated in the first automobile race in 1887 and four separate London-to-Brighton runs, for $3.5 million in 2007.

The identity of the new owner was not given.

US media reports noted that another car, housed at the National Motor Museum of Britain, also lays claim to the title of the world's oldest vehicle.

However, the reports said the British car, built in 1875 by Robert Neville Grenville, has only three wheels, requires someone to ride along and tend the boiler, and bears little resemblance to a modern automobile.

The four-wheeled De Dion-Bouton was constructed for the French Count De Dion - one of the founders of the company that built it. It was named La Marquise after the count's mother.

The $4.6 million price tag includes a 10 per cent buyer's premium, which goes to the auction company.

"With impeccable provenance, fully documented history, and the certainty that this is the oldest running family car in the world, La Marquise represents an unrepeatable opportunity for the most discriminating collector," the catalogue said.

"It is unquestionably and quite simply one of the most important motor cars in the world."

AFP