Finland adopts Joensuu model for urban roundabouts

Finnish municipalities are using Joensuu’s approach to urban roundabout design after years without suitable national guidance, Yle reports. Kuntaliitto published a nationwide design guide in 2024, drawing on lessons from the eastern Finnish city.

Joensuu has more than 40 roundabouts in its urban area and has built new ones regularly. City traffic systems engineer Rasmus Nousiainen says residents who once opposed them now sometimes ask for roundabouts when intersections are renovated.

The guide distinguishes urban roundabouts from those outside built-up areas. In cities, the roundabout is designed around the needs of passenger cars, while larger vehicles can pass by driving partly over the central island. The narrower layout encourages lower speeds, Nousiainen says, while helping traffic move more smoothly.

It also recommends placing pedestrian crossings and cycle paths a few metres from the circulating roadway, making people walking and cycling easier for drivers leaving the roundabout to see.

Joensuu’s roundabouts have reduced collisions, according to the article. At the intersection of Kosti Aaltosen tie and Marjalantie, reported crashes stopped after a roundabout was completed in 2021. Eight crashes had been reported to emergency services there between 2007 and 2020.

Measurements cited by Nousiainen found that vehicles leave urban roundabouts at an average of 22 kilometres per hour, compared with 44 kilometres per hour at traditional roundabouts. The roundabout on Karjalankatu, completed about a year ago, has had no serious crashes so far.

Tampere University professor of practice Kalle Vaismaa says the newer designs are particularly safer for cyclists and hopes municipalities will widely adopt the guide. Tampere, Riihimäki and Porvoo have expressed interest, and Helsinki has already used it, Nousiainen says.

Roundabouts are not suitable for every intersection, particularly the busiest ones, where traffic lights are still needed.