Cambridge is poised to become the first U.S. city with a municipal law requiring construction of a network of permanent, protected bike lanes.

The City Council is expected on April 8 to pass the so-called Cycling Safety Ordinance, which would require Boston’s neighbor to install permanent, protected bike lanes whenever a roadway within the city’s bicycle plan is reconstructed under a five-year plan Cambridge has for upgrading its sidewalks and streets.

In practical terms, that means the regular addition of permanent protected bike lanes in Cambridge as the larger sidewalks and streets plan plays out. That will mean a 20-mile network—just for bikes and delineated by vertical barriers—though it’s unclear how quickly that network will go up. (An earlier version of this article said that the 20 miles could be done by the mid-2020s.)

Advocacy group Cambridge Bike Safety notes that the law will also enshrine the notion of connectivity when it comes to biking, “meaning all desired routes between major origins and destinations in the city [will be connected] and that any update to the Cambridge Bike Plan’s protected network must maintain connectivity.”

Figure 5.14 in this 2015 release from the city shows how the network will likely unfold. Thoroughfares such as Mt. Auburn Street, Concord Avenue, and Massachusetts Avenue are expected to be within the protected biking network.