They cut speed limits, changed street design, removed space for cars and generally made life harder for motorists.

Now it appears the work is paying off. Two of Europe’s smaller capital cities – Oslo and Helsinki – are reaping the rewards of committed action on making their roads safer, reducing pedestrian fatalities to zero last year.

Helsinki recorded no deaths for the first time since records began in 1960, down from an average of 20-30 a year in the 1990s. In Oslo, there were also no pedestrian or cyclist deaths in the city, which has a population of 680,000, and no children under 16 died in traffic crashes in the entire country.

In comparison, 57 pedestrians died in London in 2018; 2019 figures have yet to be released.

The Nordic achievements beg the question: what did they do to achieve such dramatic improvements?

Christoffer Solstad Steen from Trygg Trafikk, a road safety organisation in Norway, said: “[Politicians in Oslo] have chosen to make it more difficult to use a car – it takes more time to drive from one part of the city to another now and you have to pay money to use the road much more than you used to.”

In 2017 there was a 70% increase in tolls across the city, in plans spearheaded by the Labour and Green parties, which led to a 6% decrease in traffic.

Car parking charges were also increased – by 50% in downtown Oslo and 20% elsewhere – although thousands of spaces have now been wiped out to make room for 35 miles of new cycle lanes.

The city has reduced speed to a maximum of 30km/h outside schools and started trialling “heart zones”, where driving is banned in areas around schools. Officials in Oslo hope to create 100 of these zones over the next four years.

There has been some opposition to the changes, admits Arild Hermstad, Oslo’s vice mayor for environment and transport – particularly when it comes to banning cars from certain areas of the city.

However, he thinks when people become accustomed to the new set-up, they see the benefits: “When it actually starts happening and people see that it’s working, then no one wants to reintroduce the cars into these roads. So I think more and more people are seeing that this is actually good for the city,” he said.

“We want to reduce the overall car traffic in Oslo by 30% by 2030. It’s a hard goal, but we think it will be good for the city as well.”

Similar traffic reduction tactics have been employed in Helsinki, where speed limits have been tightening for decades and were reduced again last year. Now the speed limit is 30km/h on most residential streets and the city centre, 50km/h on main streets in suburban areas and 40km/h on those in the inner city.

“Of course, it’s not only a question of speed limits, although I think all our specialists do say that is the most important single thing affecting traffic safety,” said Anni Sinnemäki, the deputy mayor of urban environment in Helsinki.

“In the last few years, we have also focused on how we build the street environment. Streets are being better divided between pedestrians, cycle lanes and cars – the car lane is not the widest possible.”

Along with narrower driving lanes, Helsinki has also built dozens of roundabouts and installed speed bumps since the 1990s to reduce speed.

The wider picture across Europe shows a sharp difference in road safety. From 2015 to 2017, the average number of road deaths on urban roads per million urban inhabitants was 10.9 in the UK. In Norway it was just 5.3, the lowest in Europe, while in Finland it was 16.9. The countries with the highest rates of urban road deaths were Romania with 105.2, Croatia with 87.9 and Serbia with 73.8.

Norway and Finland have implemented Vision Zero, a set of principles and policies aimed at eliminating serious injuries and fatalities involving road traffic. The project shifts responsibility for crashes from road users to the designers of the road system – if one occurs, it is up to authorities to ensure that it does not happen again.

The initiative has been taken up across the world with varying levels of success. Sadiq Khan signed London up in 2018, but Norway has been working towards it since the 1990s.

The goal hasn’t been achieved yet, however. Although both cities recorded zero pedestrian fatalities in 2019, in Helsinki three drivers died in traffic crashes last year, while in Oslo one driver died. A pedestrian has also been killed in the city this year.

In Norway, there has also been a renewed focus on road safety education in schools and maintaining a tough driving test.

Hermstad said: “For many years, the driver education system has focused a lot on road safety. And also strict regulations and road rules that prioritise safety, maybe more here than in many other countries.”

Steen added: “It’s easy to build yourself out of problems but it is more difficult to get people to understand that this is important and make them act in a more secure way.

“I’m not saying that we have managed to achieve that goal, but it’s one of the things we have been focusing on for many years in Norway and probably one of the reasons why things are getting better.”