Lane-Level Access Restrictions for Public Transport Routing
Symptoms
--------
A road displayed as one-way is routable in the opposite direction for Bus routing.
Taxi routing appears to ignore one-way restrictions.
Car and Bus routes differ on the same road segment.
Routing results appear inconsistent with map visualization.
HERE map data and the public transport routing engine fully and correctly take lane-level access restrictions into account when planning routes for public transport modes such as buses or taxis.
This article explains why a road segment that is visually rendered as one-way on the map may still be routable in the opposite direction when the transport mode is set to Public Transport or Bus.
The road segment highlighted in Figure 1 is displayed to users and customers as a one‑way street in the south direction.
However, in reality:
In the north direction, the road consists of a single lane only.
This lane is exclusively reserved for buses and taxis.
General traffic is not allowed to use this lane in that direction.
Although the map rendering shows the link as one‑way, the lane-level access characteristics stored in HERE data indicate that public transport vehicles are allowed to travel in the opposite direction.
### Routing Engine Behavior
As a result:
When routing mode is set to Car, the street is treated strictly as a one‑way street in southbound direction. Note: If the route is not displayed after opening the link, please click Send in the bottom‑right corner of the page to trigger route calculation
When routing mode is set to Taxi or Bus, the routing engine:
+ Recognizes the bus/taxi-only lane
+ Treats the link as bidirectional for the allowed transport modes
Therefore, even if the road appears visually as one‑way, it is correctly considered two‑way by the routing engine for buses and public transport.
This behavior is intentional and expected, and reflects the accurate modeling of real-world lane access restrictions rather than a data or routing error.
Here some additional figures illustrate routing behavior differences for Public Transport (Taxi and Bus) and private car
Expected Behavior
-----------------
Car routing follows the one-way restriction shown on the road.
Bus and Taxi routing evaluate lane-level access permissions.
Vehicles authorized to use dedicated Bus/Taxi lanes may travel in the permitted direction.
Route results may differ from the visual map representation when lane-level attributes apply.
Unexpected Behavior
-------------------
Bus or Taxi routing ignores valid lane access permissions.
Routing allows travel on lanes that are prohibited for the selected transport mode.
Car routing uses the reserved Bus/Taxi lane against access restrictions.
Root Cause
----------
The road contains a dedicated lane that is restricted to Bus and Taxi traffic in the opposite direction. While the map visualization displays the road as one-way for general traffic, routing calculations evaluate lane-level access attributes and allow travel for authorized transport modes.
Impact
------
Customers comparing route results with the visual map display may incorrectly assume that the routing engine is ignoring one-way restrictions. In reality, the route is calculated using additional lane-level access information that is not fully represented in the map rendering.
Recommended Actions
-------------------
Verify the selected transport mode when reviewing route results.
Review lane-level access restrictions using HERE map data inspection tools where available.
Compare routing behavior across Car, Bus, and Taxi transport modes.
Use Routing API responses as the authoritative source for route accessibility.
* Refer to the provided routing examples when validating expected behavior.
Keywords
--------
Routing API, Routing V8, Bus Routing, Taxi Routing, Public Transport Routing, One-Way Road, Lane-Level Access, Access Restrictions, Transit Lanes, Dedicated Bus Lane, HERE Map Data, Route Calculation, Transport Mode, Bidirectional Routing, Public Transport
Updated 3 days ago