An epic adventure – and an architectural challenge

London, 2011: Bompas & Parr flooded part of Selfridges' roof to create a crystal island and boating lake in celebration of the UK launch of Truvia sweetener, derived from the stevia leaf.

The Truvia Voyage of Discovery allowed visitors to enjoy their first taste of stevia, which is, astonishingly, 200 times sweeter than sugar.

The project encompassed an emerald green boating lake with a Crystal Island at its centre, a gushing waterfall, with 12 rowing boats and a life guard, with guests surrounded by 12,000 stevia plants.

Alongside, a fleet of specially commissioned creative outputs: cocktails by ECC; design by Studio Toogood; uniforms by Tour de Force; tropical soundscapes by Dom James; tea by Rare Tea Company and coffee by Caravan – all six storeys above London's busiest shopping street.

Photography by Nathan Pask, Beth Evans, Nick Westby and Ann Charlott Ommedal. Illustration by Tour De Force.