The Prophet's Mosque in Medina has a limited amount of space, and overflow worshippers often pray in the massive courtyard. To protect them from the punishing sun, German engineering firm SL Rasch was hired to create a shading solution. "When it comes to transforming a paved, sun-drenched space into a shady oasis," the company writes, "lightweight textile structures are second to none."

With that in mind, the company devised a series of elegant towers that are essentially gigantic motorized umbrellas.

"SL Rasch developed a new type of umbrella that features an innovative folding arm system with six hinges. The umbrellas are also two different heights. This allows their membranes to be overlapped to create a continuous canopy."

"Besides providing lasting protection from the weather and UV radiation, the specially developed Teflon fabric is dirt-repellent and wear-resistant, as well as delivering the crucial benefit of high tensile strength. The material is also extremely smooth and supple and falls in attractive folds. The tapes and seams are accentuated in colour to add a floral quality to the funnel-like membranes."

"When folded, the membranes are protected from the sand and wind by cladding panels made of a glass-fibre-reinforced composite. They are decorated with fine mosaics made of weatherproof glass tiles that blend in with the architecture of the mosque."

"The convertible shading roof provides a sheltered space of exquisite architectural quality for up to 250,000 people. The play of light created by the translucent membrane vaulting creates a unique atmosphere in this special place and invites pilgrims to linger, pray and interact."

"The umbrellas are arranged in groups of between two and 15 units. Gaps in the main axis permit an unobstructed view of the mosque and minarets and thus provide orientation. This unique lightweight architecture – the biggest convertible roof in the world – earned SL Rasch the generously endowed Abdullatif-Al-Fozan Award for Mosque Architecture."