Berlin - Prinzregentenstraße is one such case. Every morning the designated "bicycle street" or Fahrradstraße is packed with commuters pedaling to work. And yet, time and again, cars end up in the stream of bikes. Why? One reason is that TomTom sat-navs are unaware of the cycle street.

Berlin non-profit AlgorithmWatch took a closer look at the TomTom and Google Maps navigation systems and checked whether they comply with the rules in Berlin. The researchers found that while calculating the shortest route between two places it often directs motorists into cycle streets, where they have no business being - and not just in Prinzregentenstraße.

As the name suggests, "bicycle streets" are primarily intended for cyclists. Cyclists are even allowed to cycle side by side - normally a verboten activity. Other vehicles are only allowed to use the streets if explicitly demarcated, and it's often limited to local residents as on Prinzregentenstraße. The speed limit is generally 30 kph and the bike-only streets are usually unsuitable for through traffic.

Bicycle streets not recognised by navigation software

Bicycle streets have existed in Germany since 1997. The first Berlin street of this kind, Alberichstraße in Marzahn, received the designation in 1998. Many others have since been added. Prinzregentenstraße in Charlottenburg-Wilmersdorf has been a bicycle street since 2010. Companies have had plenty of time to update their data.

Cyclists have had priority on Bergmannstraße in Kreuzberg since 2011, but this also apparently remained hidden from the algorithms. The tests showed that the software recommended travelling via Bergmannstraße when motorists wanted to get from Heimstraße to Südstern. In a third example, also in Kreuzberg, both systems recommendded taking the bicycle street Körtestraße to get from Hasenheide to Dieffenbachstraße. 

Journalist and data expert Nicolas Kayser-Bril spent weeks taking a closer look at the route suggestions of the two types of software. He assumes that there are numerous other cases in Berlin where motorists are directed into Fahrradstraßen.

"The fact that these service providers are not able to mark a bicycle street as a bicycle street for more than 10 years - in the case of Bergmannstraße - shows that respect for bicycle streets is low on their priority list," said Kayser-Bril.

Database errors

Both Google and TomTom referred to errors in their databases when asked by AlgorithmWatch. A TomTom spokesperson told AlgorithmWatch that several of the Berlin streets that were incorrectly labelled in their database had been fixed but the update could take up to six months to be complete.

It appears the Berlin authorities are not entirely blameless. District authorities are responsible for creating new bike streets and are also charged with the task of communicating such changes to the public. Kayser-Bril's research suggests that they've been ineffective in doing so.

For the cycling association ADFC (Allgemeiner Deutscher Fahrrad-Club), it's a big issue.

"Bicycle lanes not only invite people to switch to cycling in a climate-friendly way, they are also a good way to keep disruptive, noisy motor vehicle through-traffic out of neighbourhoods," said Lisa Feitsch, the club's Berlin press spokesperson.

"Solutions are needed here; routing services are service providers and must not be allowed to undermine the city's efforts to increase traffic safety and improve the quality of life for residents. We will check what legal options are available to us."

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