In 2002, Heatherwick Studio was commissioned to design a bridge as part of the redevelopment of Paddington Basin. The new bridge would need to carry pedestrians across a narrow inlet of the main canal, while also allowing the passage of boats when necessary.

The studio, founded by acclaimed English designer Thomas Heatherwick, could have gone with a more traditional option, such as a swing bridge, a lifting bridge, or a rigid retractable bridge. But instead, they designed a structure that, as far as we know, is the only bridge of its kind in the world.

Opened in 2004, the Rolling Bridge uses a curling motion to extend and retract across the span of the canal. It’s a wonderfully organic motion; think of a leaf unfurling, or a caterpillar curling up, or the fingers of your hand closing to form a fist, and you’ll have a good idea of how the bridge opens and closes.

The Rolling Bridge is about 39 feet long and consists of eight triangular sections. When extended and lying flat across the canal, it looks like a fairly nondescript rigid bridge. But it is only attached to one bank. When put into action, hydraulic rams set into the bridge’s balustrade cause the triangular sections to lift up and close in together. As they do so, the bridge curls up as it moves towards the bank. The two ends eventually meet, forming an octagon once fully retracted.

The bridge closes in near silence, which adds to its elegance, and can also be stopped at any point during its extension or retraction. Once fully retracted, it looks like a sculpture rather than a bridge, and not dissimilar to an old water wheel.

Seeing it in motion, however, requires some planning. The bridge was initially scheduled to unfold across the canal every Wednesday and Friday at midday and every Saturday at 2 p.m. At the moment, however, its operation seems to be limited to Fridays at noon.