Separated Bicycle Facilities

What is a Separated Bicycle Lane?

The term “separated bicycle facility” or “separated bike lane” is generally used to refer to bicycle facilities that follow street alignments with a physical separation between the bicycle travel area and the motor vehicle travel area, often through barriers or grade separation. They are located between the street and the sidewalk, or between the parking lane and the sidewalk, and may also be referred to as protected bike lanes, raised bike lanes, or cycle tracks. They incorporate the convenience of riding on the street with the advantages of physical separation from motor vehicle traffic. Motorists are less likely to drive or park in separated bicycle lanes, making bicyclists who are apprehensive about riding in the street more likely to ride in these types of facilities, and less likely to ride on the sidewalk where pedestrians are. Most designs reduce or eliminate the risk of dooring, and research shows that separated bicycle lanes increase safety. Significantly, separated bicycle facilities provide the necessary support for a greater range of people, including children and those who are traffic-averse, enabling more people to choose to ride a bicycle. They thereby help the City’s goal of creating a more equitable city for people of all ages and abilities.

Locations of separated bicycle lanes throughout Cambridge

cycle tracks - kids

Benefits of Separated Bike Lanes

  • Increase comfort and safety for bicyclists through separation from motor vehicles to create a more path-like experience.
  • More comfortable and accessible for people of all ages and abilities, children and the elderly alike. They attract new riders at all levels who otherwise may not bicycle, and therefore increase ridership more so than bicycle lanes.
  • Reduce crashes, overall injury risk, and fear of collisions with over-taking vehicles at mid-block.
  • Remove bicyclists from the door zone, eliminating the risk of “dooring” and potentially being struck by a motor vehicle.
  • Reduce or eliminate potential obstructions that occur commonly in bicycle lanes, such as motorists parking or driving in the lane.
  • Providing a dedicated space for bicyclists improves clarity about expected behavior for all modes of travel.
  • Enhance the pedestrian environment by creating a buffer between pedestrians and vehicle traffic adjacent to the sidewalk.
  • Narrowing the roadway width, either physically or visually, through the installation of cycle tracks can have a traffic calming benefit and help to create a more human-scale environment.
  • Intersection designs can reduce or separate conflicts with motorists.
  • Provide a better air quality environment for users than riding in the roadway. The increased separation from motor vehicle traffic also provides better air quality for pedestrians.
  • Provide economic benefits—they attract more bicyclists than standard bike lanes which results in more productive workers and more spending at local businesses.

Cambridge Locations Concomitant with Construction

The City of Cambridge was one of the first cities in the United States to design and construct cycle tracks. In 2004, a raised cycle track was installed on Vassar Street from Main Street to Massachusetts Avenue, with full construction to Audrey Street completed in 2009. A second facility was later installed on Concord Avenue from Alewife Brook Parkway to Blanchard Road. Separated bicycle facilities are a star element of the state-of Western Avenue Reconstruction Project, which won a Best Bicycle Lane of the Year award from People for Bikes.

There are many additional projects in progress: grade-separated separated bicycle facilities are part of the Binney Street/Galileo Galilei Way reconstruction. Separated bike lanes will also be constructed on Ames Street (Broadway – Memorial Drive) and on Main Street (Longfellow Bridge – 3rd Street) following the Longfellow Bridge reconstruction. Raised separated lanes will be created on Monsignor O’Brien Highway with that roadway reconstruction. 

As a Driver, What am I Supposed to do?

  • Do not block the bike lane: You may never drive or park in any bike lane, including separated bike lanes
  • Watch for bikes when turning: Please make sure to look for and yield to bikes when entering or exiting a driveway or when turning at an intersection. You should always do this, at every driveway or intersection.

How Should Cyclists Use Protected Bike Lanes?

  • Separated bike lanes afford the same access as regular bike lanes. As always, pay special attention at driveways and intersections for turning cars.
  • Slower cyclists are encouraged to comfortably position themselves to the RIGHT side, so they may be passed by faster cyclists on the LEFT.

street code separated bike lane page

For More Information

For more extensive information and technical documents about Cycle Track/Separated Facility Design:

For some interesting reports of bike facilities from around the world, check out:

Staff Contact

For more information about bicycling in Cambridge, please contact Cara Seiderman,, at 617/349-4629.