Apart from giving the mosque a gritty complexion, Tepebasi's concrete has freed the architect from the engineering challenges which architects in stone had to grapple with, reducing Sinan's structural brilliance to mere ornament.

ECONOMIST: The architecture of mosques

Stand in the center of the rotunda and gaze up to the heavens through the eight-meter-high oculus at the center of the five-ton concrete dome --a stunning feat of ancient engineering, still intact after two thousand years.

CNN: 24 hours in Rome: Pizzas, piazzas and 'la dolce vita'

Its dashing architecture, like a giant curved earthworm lined with a concrete honeycomb, was widely seen as a showpiece of French engineering and design flair.

ECONOMIST: The aftershocks from a collapsed airport terminal

Kahn admitted that ancient Roman vaults and arches were his inspiration, and by combining them with advanced engineering and a simple palette of materials concrete, travertine and white oak he created a place that is of the present but also invokes an ancient past.

WSJ: Ancient Modernism | 'Louis Kahn: The Power of Architecture' | Vitra Design Museum, Germany | By Colin Amery

David Bartram head of highways and engineering at Derby City Council said the work had been vital after lumps of concrete up to 9in (22cm) in size had fallen from the Derwent Underpass in December.

BBC: Derby ring road works continue to disrupt traffic

He briefly chatted with civil engineering senior Alicia Veach, who is planning to use the 3D printers to create miniature prototypes of the concrete canoes she and her team use in racing competitions around the country.

ENGADGET: The future of higher education: reshaping universities through 3D printing