If you were to associate Volkswagen with one particular fuel-efficient technology, it'd probably be diesel.

VW's range of diesels is expanding in the U.S, but it's massive in Europe--accommodating a market where over 50 percent of buyers choose diesel vehicles.

As a result of Europe's love of diesels, they get some fairly interesting models denied to the U.S. With the Golf, that means a sporty GTD, and the model you see here--the BlueMotion.

Volkwagen's BlueMotion brand launched on the smaller Polo model over a decade ago, and has always represented the most efficient version of a particular model. In this case, it's a Golf that achieves 73.5 mpg on the European combined economy cycle.

Even if we take away the usual 15-20 percent discrepancy to get a figure more akin to EPA testing, the Golf BlueMotion is still near-59 mpg car--and that's combined economy, remember.

Real world results will naturally vary. That 60-70 mpg may well be achievable in steady freeway driving, but you could expect less in city traffic or travelling at sustained higher freeway speeds.

But how does it manage such high numbers?

With fairly simple techniques, as it turns out. While U.S-bound VW diesels all use 2.0-liter engines, a smaller 1.6-liter unit is quite common in Europe. The engine in the BlueMotion is newly-developed.

It puts out a modest 110 horsepower, and a more healthy 184 pounds-feet of torque between 1,500-2,750 rpm. Performance therefore isn't as strong as the 2.0-liter TDIs, but some may question just how much performance you need in a car designed largely to travel at constant speeds over long distances.

It really can travel long distances too - at the European combined figure, its 13.2-gallon tank is enough for 970 miles of range--enough to travel from Los Angeles to Portland.

The BlueMotion uses other common eco-tweaks too--low rolling-resistance tires, a blocked grille, a lower ride height, small spoilers to direct airflow, flat underfloor panels and aerodynamic wheels. This is an ecomodded car straight out the factory.

It's also lighter than previous Golfs thanks to VW's new platform, while long gear ratios and stop-start technology boost fuel efficiency at high and lower speeds alike.

All in all, it makes us wonder--just what would it take for VW to sell a car like this in the U.S.?

The Golf BlueMotion was launched at the 2013 Geneva Motor Show--you can check out more from the show on our dedicated page.

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