This new software maps out a better bike network for your city

In most cities, bike networks are rolled out in disconnected pieces. A bike lane on one street might not reach the next part of a route, so you can't necessarily ride safely across town.

A new set of software tools helps planners, bike advocates, and citizens design more complete networks, automatically filling the gaps in existing infrastructure or creating the whole thing from scratch.

Introducing BikeNetKit

Called BikeNetKit, the free, open-source software is based on eight years of research on bicycle infrastructure at Denmark's IT University of Copenhagen.

When you type in a city name, the software pulls street data from OpenStreetMap, including a map of existing bike lanes. (Getting started requires a little technical knowledge: You have to know how to use Python, and then have to enter a few lines to install and run the algorithms.)

"Planners mostly think about the small picture-what if I add a lane here? What's on the right side and left side? But they don't think about the network and the whole city," says Michael Szell, an associate professor at the IT University of Copenhagen, who led the project. "Our methods are built on network science methods that look at the city from a big picture."

Building a network from scratch

One of the tools, called GrowBikeNet, can build a network from scratch-particularly useful in the U.S., where most cities have sparse bike lanes.

The algorithm creates a grid of "seed points" over a city. It connects those points to any existing bike infrastructure, drawing a new map of suggested bike routes.

"The first links that are suggested are the links where you expect the most cyclists to ride," Szell says. Rolling it out this way would create a functional network from the outset, with strong connections already in place.

Planning with data and fixing gaps

Users can upload additional data to help plan a network-for example, where traffic crashes have occurred in the past, or where people typically travel each day. The software also gives the option to plan bike lanes around schools.

Another set of tools includes:

• Superblockify, which suggests places to add car-free neighborhoods
• LinkBikeNet, which connects gaps in otherwise well-connected networks
• FixBikeNet, which tells cities which gaps are most important to fix first

The tools don't specify what the bike infrastructure should look like. Instead of bike lanes at the side of the road, for example, some streets could be dedicated solely to people on bikes and pedestrians.

Of course, that's the opposite of most transportation planning now, which focuses on the flow of cars. "Planning for cycling is always some kind of afterthought," says Szell.

The BikeNetKit website includes hundreds of analyses of European cities, from growing a new bike network in Kyiv, Ukraine, to fixing gaps in Copenhagen's network, to potential car-free neighborhoods in Berlin. To try it out yourself, the open-source code is available on GitHub.