A Class IV bikeway, often called a protected bike lane or cycle track, is a type of bicycle facility designed to physically separate people biking from vehicle traffic.

Unlike painted bike lanes, Class IV bikeways use vertical or horizontal barriers — such as curbs, flexible posts, inflexible physical barriers like planters, or parked cars — to create a protected space for cyclists.

Key features of a Class IV bikeway include:

• Physical separation from cars using barriers or raised elements
• Greater safety than standard bike lanes, especially on busy streets
• Dedicated space for people biking, often designed for riders of all ages and abilities
• Improved crossings and visibility at intersections through striping, signage and signals

Each direction typically has a five-foot riding space, creating a 10-foot-wide bikeway separated from vehicle lanes by a buffer and vertical delineators.

Transportation agencies often use Class IV bikeways on high-traffic corridors where traditional bike lanes may not feel safe or comfortable, or where space constraints make other designs impractical.

Class IV bikeways are considered part of a broader “complete streets” approach, which aims to balance the needs of people walking, biking, driving, and using transit.

Source: Class IV Bikeway Guidance (California Department of Transportation Division of Design)