The elegant Sackler Crossing spans one of the lakes in London’s Royal Botanic Gardens at Kew. Created as part of a new route that leads visitors through a previously under-used area of the gardens, its graceful structural design and gently curving form complement the natural contours of this sensitive setting, a World Heritage Site which is home to countless rare and historic plants.

The S-shaped bridge consists of a deck made of 564 black granite sleepers lined by around 1,000 bronze posts which form the balustrades. The 100mm gap between them creates an intriguing ambiguity between solid and transparent, with the gaps appearing and disappearing depending on the angle of approach.

The bridge’s route across the water was carefully chosen to avoid damage to tree roots and minimise other environmental impacts on the gardens. The deck is intentionally very close to the waterline so that the whole structure appears to float just above the lake. An extra aesthetic dimension has been added by installing LED lights at the base of the posts to illuminate them after dusk.

The lake was fully drained and a causeway installed to enable construction of the bridge. Nine driven steel piles were inserted into the floor of the drained lake and extended as columns. Upon them rests 30 tonnes of structural steelwork that forms a framework onto which the granite deck is bolted.