World's longest pedestrian bridge opens after £126m project and it's near UK

A gigantic bridge connecting two islands has finally opened – and there's not a car in sight. The colossal 1,200-metre (4,000ft) structure is believed to be the world's longest pedestrian bridge. Near the Finnish capital of Helsinki – which is just a three hour flight from London – the bridge connects the islands of Laajasalo and Korkeasaari. It is also Finland's longest and tallest bridge. As part of a drive to sustainability the mammoth structure is the “world's longest bridge dedicated exclusively to trams, pedestrians and cyclists,” explained a spokesperson for designers Knight Architects. “Unusually for a structure of this scale, Kruunuvuori Bridge prioritises sustainable movement having been conceived exclusively for trams, pedestrians and cyclists,” the firm said. “This fundamental decision redefines the role of the bridge from a piece of transport infrastructure to a civic space in its own right.” The €150m (£126m) Kruunuvuori bridge is one of six being built as part of a £505m project which will extend the tram network for around six miles from the city centre to Laajasalo, where a new major housing development is under construction. It would take an average person around 15 minutes to walk across the bridge: “As the longest and tallest bridge in Finland, its central diamond is a major new addition to Helsinki’s skyline,” architect Tom Osborne told Newsweek . “The bridge is a vital link to a new community and a catalyst for sustainable growth.” The bridge’s width varies from 49 feet to 62 feet – the widest points being around the pylon – with a 65-foot maximum clearance. The bridge is not only huge, but its planned lifespan is significantly longer than that of its rivals. “120 years would be a typical design life for bridges of this scale,” Tom said, promising that the Kruunuvuori Bridge should endure for around 200 years. “It is a big bridge and therefore a big investment. But taking a 200-year position on the returns of that investment – in both financial and climate terms – shows that big projects need to be paired with a long-term view." He told New Civil Engineer that there was a good reason for building such a tall structure in what is generally quite a low-lying city: ““Building something that is quite tall and distinctive was perhaps not the obvious thing but there was a good reason. Having a central tower allowed the skyline at deck level to be much less cluttered than having many smaller towers.” He added: “The water gets quite deep on either side of the tower, and so having smaller spans would have been more expensive.” The architects have had to take the hard Finnish winters into account when designing the long chain of bridges. In a press release, Knight Architects explained that the bridge’s stay cables are "designed to remain in constant slight motion" whenever the wind blows – helping prevent ice buildup. The cables are encased in a textured plastic coating that cause ice to break into fine particles rather than forming into large icicles.. The bridge will also incorporate a sophisticated wind warning system, and when strong gusts are detected a warning will be displayed on electronic signs at each end. Osborne added that he hopes the bridge will be the first of a new generation of structures that are built with an eye to the future: “Over the next 200 years, I hope this diamond becomes not only a symbol of its place, but a symbol of a shift towards more sustainable ways of living,” he said.