# Road Link attribution
The [Road Link Feature Type](/osngd/data-structure/transport/transport-network/road-link.md) can be found in the OS Transport Network Collection of the OS NGD Transport Theme. This feature type represents line geometry for Great Britain’s road system and provides a routable network when used in conjunction with the [Road Node Feature Type](/osngd/data-structure/transport/transport-network/road-node.md).
Attribution is provided against Road Links (data schema version 5.0 onward) to indicate the presence of bus lanes; you can use the data to see if there is bus lane infrastructure present along a road or path and quantify how much there is.
{% hint style="info" %}
Please note that bus lane infrastructure is often disconnected in the real world, which will impact the continuity of the Bus Lane Presence attribution.
{% endhint %}
Example image showing bus lane presence along a Road Link. A background map has been included to provide context.
## Key attribution
Key Bus Lane Presence attribution on the Road Link Feature Type includes:
* **Overall Presence and Percentage**: Indicate the length (in metres) and the percentage of the Road Link that has a bus lane present on it. ([Presence Of Bus Lane Overall M](/osngd/data-structure/transport/transport-network/road-link.md#presenceofbuslane_overall_m) and [Presence Of Bus Lane Overall Percentage](/osngd/data-structure/transport/transport-network/road-link.md#presenceofbuslane_overallpercentage) attributes.)
* **In Direction Presence and Percentage**: Indicate the length (in metres) and the percentage of the Road Link that has a bus lane present on it that can be traversed in the direction of digitisation of the Road Link. ([Presence Of Bus Lane In Direction M](/osngd/data-structure/transport/transport-network/road-link.md#presenceofbuslane_indirection_m) and [Presence Of Bus Lane In Direction Percentage](/osngd/data-structure/transport/transport-network/road-link.md#presenceofbuslane_indirectionpercentage).)
* **In Opposite Direction Presence and Percentage**: Indicate the length (in metres) and the percentage of the Road Link that has a bus lane present on it that can be traversed against the direction of digitisation of the Road Link. ([Presence Of Bus Lane In Opposite Direction M](/osngd/data-structure/transport/transport-network/road-link.md#presenceofbuslane_inoppositedirection_m) and [Presence Of Bus Lane In Opposite Direction Percentage](/osngd/data-structure/transport/transport-network/road-link.md#presenceofbuslane_inoppositedirectionpercentage).)
{% hint style="info" %}
### Note about percentages
Please note that percentage values are given to the nearest whole percent (for example, 15% not 14.8%). In cases where only a very small length of Bus Lane is associated with a Road Link, the percentage value will be rounded to 0% if the length is less than 0.5% of the length of the Road Link; therefore, you may see a small number of instances where a length in metres is populated but the percentage is 0%.
{% endhint %}
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