Art lovers attending an exhibition opening in Bregenz, Austria were treated to an unusual sight: an ensemble of eleven Porsche 911s cast in concrete. Artist Gottfried Bechtold tells of his interest in Porsche for the past 35 years, and his reason for choosing it as his model.

"A concrete Porsche is incongruous, almost a contradiction in terms," he says. "An automobile capable of going 300 km/h (185 mph), the very embodiment of speed, is rendered immobile."

The eleven sculptures weigh in at 3,300lbs each, exactly eleven times as heavy as a regular Porsche. They were cast with a special concrete blend. "We went to the limit of what is technically possible," says Bechtold. Read more about his process here (PDF).

View more uncommon concrete items.