Construction Of Finland’S Biggest Bridge Sees Completion Of 135M-Tall Diamond-Form Pylon

Construction on Finland’s tallest and longest bridge has reached a crucial milestone with the completion of its distinctive 135m tall diamond-form pylon.

This key structural feature is part of the Kruunusillat (Crown Bridges) scheme in Helsinki, designed by Knight Architects and engineering consultancy WSP Finland.

The 1.2km long bridge will link Helsinki’s city centre with the new island suburb of Laajasalo, a move aimed at facilitating the development of a new waterside community.

The primary feature of the main span, the Kruunuvuorensilta crossing, includes a slender 135m diamond-shaped pylon that supports two cable-stayed spans, each measuring 250m in length.

The pylon's diamond-shaped design not only serves a structural purpose but also pays homage to the historical crown ownership of the Helsinki bay area

Currently, cables are being affixed to the pylon, after which the temporary supports will be removed.

The diamond-shaped design not only serves a structural purpose but also pays homage to the historical crown ownership of the Helsinki bay area, and it is anticipated to become a recognisable symbol of the city. Upon completion, it will stand as the tallest bridge structure in Finland.

In a notable departure from traditional bridge designs, the Kruunusillat project will be car-free, instead supporting a new light rail line that will enhance connectivity to Helsinki’s tram network, as well as providing pathways for cyclists and pedestrians.

This initiative aligns with Helsinki’s broader sustainability goals, which include a vision to become a car-free city by 2030. Around £1bn worth or expansions to its tram network are in different stages of development.

The bridge will be car-free, instead supporting a new light rail line and providing pathways for cyclists and pedestrians

The Laajasalo area is being master-planned as a largely car-free community to encourage sustainable public transport and active mobility.

Knight Architects and WSP Finland were awarded the project after winning an international design competition in 2013. Construction began in late 2021, and the project is set for completion later this year.

Construction started in 2021 and is expected to be completed this year

Knight Architects director Tom Osborne said: “We have been working on Kruunusillat for over a decade, so it’s fantastic to have reached this critical milestone in its delivery. The distinctive diamond now provides Helsinki with an instantly recognisable addition to its skyline, that we hope soon comes to symbolise not only the identity of this wonderful city, but it’s continued efforts to shift to sustainable transport modes.

“At Knight Architects, we strive to design bridges that do much more than just connect A to B. We aim to create beautiful structures that respect and enhance their environment and generate lasting value, and Kruunusillat is a great example of that approach in action.”

All photos by Aarni Salomaa and provided by Knight Architects

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