What is an advisory lane?
An advisory lane is a zone on a road that is indicated for bikes (and sometimes pedestrians) to use, but which motor vehicles are also expected to use in the normal course of travel because the remainder of the road is not wide enough for motor vehicles in opposite directions to get by without encroaching on the indicated bicycling zone.
A road with advisory lanes, called an advisory lane road (ALR), has no markings that divide the road into motor vehicle travel lanes; thus, an ALR cannot be a multilane road, and cannot have a marked centerline. On a Dutch ALR, the space in the middle between the bicycling zones is not intended to be taken as a motor vehicle lane (is undesignated space/zone), because motor vehicles are allowed to use the full width of the road. The width of that central zone can vary from as little as 2 ft (0.6 m) to as much as 18 ft (5.4 m).
Types of Advisory Lane Roads
Advisory lane roads can be broadly split into 4 categories. Unmarked advisory lanes, striped suggestion lanes, and advisory legal bike lanes are iterations of the same concept, while bike streets are used in areas with higher bike volumes than vehicle volumes.
Unmarked Advisory Lanes
The bicycling zone is indicated by a different pavement type or color, without any lane lines or bike symbols.
Striped Suggestion Lanes & Advisory Legal Bike Lanes
Advisory lanes marked with broken white lines, with or without any bicycle symbol on the pavement.
Bike Streets (fietsstraten)
A street designated primarily for bikes with bike areas on either side of the street designated by color or material.