# Site Access Location

Feature which has a point geometry and represents the locations where pedestrians and / or vehicles can enter or exit a site.

## Data schema versioning

The following table provides details about this feature type’s data schema versions, including the reasons behind the changes and the related launch date when each version went live. 

### Data schema version table

<table><thead><tr><th width="118.5555419921875">Version ↓</th><th width="161">Launch Date</th><th width="140.6666259765625">Latest Date</th><th>Change</th></tr></thead><tbody><tr><td>2.0</td><td>27 March 2025</td><td><code>Ongoing</code></td><td>Major version increment adding new Access Purpose, Accessed Network Node Feature Type, Accessed Network Node ID, and Distance To Network Node attribution.</td></tr><tr><td>1.1</td><td>28 July 2025</td><td><code>Ongoing</code></td><td>Minor version increment that removes the query and download filters from the Description attribute as this attribute supports only a single value.</td></tr><tr><td>1.0</td><td>03 October 2022</td><td>27 July 2025</td><td>Initial launch of the Site Access Location Feature Type.</td></tr></tbody></table>

Please see [Data schema versioning](https://docs.os.uk/osngd/getting-started/os-ngd-fundamentals/data-schema-versioning) for in-depth information about data schema versioning in the OS NGD.

## Temporal filtering

Temporal filtering allows you to order a one-off snapshot of data from the OS NGD from a current or past date. It is an optional step when you create a new data package in OS Select+Build (the OS NGD download service).

The earliest and latest dates on which you can request a one-off snapshot of a date in the past for this feature type's data schema versions are indicated in the [Data schema version table](#data-schema-version-table) above. Please note that any data temporally filtered earlier than the specified launch date indicated in the table for the data schema versions may contain data inconsistencies.

More information about temporal filtering on OS NGD feature types is available from the [Getting started with temporal filtering guide](https://docs.os.uk/osngd/getting-started/downloading-with-os-select+build/getting-started-with-data-packages/getting-started-with-temporal-filtering).

## Feature type attributes

The following sub-sections provide details about the attributes included with this feature type, their data types in the different output formats, and other important metadata about them.

{% hint style="info" %}

## Loading OS NGD CSV files into databases

Comma-separated values (CSV) file format is universally supported for easy ingestion into all major database products. Before loading OS NGD data contained in CSV files into a database, it is necessary to create relevant tables. Data definition language (DDL) statements for PostgreSQL, SQL Server and Oracle can be accessed in our [OS NGD Resources GitHub repository](https://github.com/OrdnanceSurvey/osngd-resources/tree/main/database-resources).

For instructions on loading CSV files, see the [Getting Started with CSV](https://docs.os.uk/osngd/accessing-os-ngd/downloading-with-os-select+build/getting-started-with-csv/loading-csv-files) guide.
{% endhint %}

### osid

Primary identifier for the feature. The OSID is a Globally Unique Identifier (GUID) and requires no centralised authority to ensure uniqueness. Note that the same OSID can occur in more than one feature type when a single feature is represented multiple times in the OS NGD.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** false
* **Max Length:** 36
* **OS NGD API – Features Filterable:** Yes
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1, 2.0

### toid

Topographic identifier (TOID) of the feature, as published in the OS MasterMap suite of products.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** true
* **Max Length:** 20
* **OS NGD API – Features Filterable:** Yes
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1, 2.0

### versiondate

Date when the version was last updated.

* **Data Types:** String (GeoJSON), Date (GPKG), Date (CSV)
* **Nullable:** false
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1, 2.0

### versionavailablefromdate

The date this version of the feature became the latest version.

* **Data Types:** String (GeoJSON), DateTime (GPKG), DateTime (CSV)
* **Nullable:** false
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1, 2.0

### versionavailabletodate

The date this version of the feature was superseded by an update or ceased to exist.

* **Data Types:** String (GeoJSON), DateTime (GPKG), DateTime (CSV)
* **Nullable:** true
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1, 2.0

### changetype

The type of change that generated a new version of the feature.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** false
* **Code List Name:** [changetypevalue](https://docs.os.uk/osngd/code-lists/code-lists-overview/changetypevalue)
* **Max Length:** 50
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1, 2.0

### description

A single descriptive value intended for a quick understanding of what the feature represents.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** false
* **Code List Name:** [siteaccesslocationdescriptionvalue](https://docs.os.uk/osngd/code-lists/code-lists-overview/siteaccesslocationdescriptionvalue)
* **Max Length:** 15
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1, 2.0

### geometry

Geometry for the feature.

* **Data Types:** Geometry (GeoJSON), Geometry (GPKG), WKT (CSV)
* **Nullable:** false
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1, 2.0
* **Geometry Type:** Point

### geometry\_evidencedate

The date on which the latest evidence was gathered to make an update if required. For example the date of collection by a surveyor or third party information received.

* **Data Types:** String (GeoJSON), Date (GPKG), Date (CSV)
* **Nullable:** true
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1, 2.0

### :new: geometry\_capturemethod

Indication of the method used to capture or produce the data.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** true
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 2.0

### geometry\_updatedate

Date when the attribute was last updated.

* **Data Types:** String (GeoJSON), Date (GPKG), Date (CSV)
* **Nullable:** false
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1, 2.0

### geometry\_source

The source organisation who provided the data.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** true
* **Max Length:** 50
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1

### theme

The OS NGD theme to which this feature belongs.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** false
* **Code List Name:** [themevalue](https://docs.os.uk/osngd/code-lists/code-lists-overview/themevalue)
* **Max Length:** 40
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1, 2.0

### accesstype\_source

The organisation that provided the information.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** true
* **Max Length:** 50
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1

### :new: access\_mode (formerly accesstype)

{% hint style="info" %}
This attribute was called `accesstype`  in data schema versions 1.0 and 1.1, and was renamed  `access_mode`  from version 2.0 onward.
{% endhint %}

{% tabs %}
{% tab title="v2.0" %}
A description of the method(s) of access normally utilised at the Site Access Location (for example, Pedestrian).

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** false
* **Code List Name:** [accessmodevalue](https://docs.os.uk/osngd/code-lists/code-lists-overview/accessmodevalue)
* **Max Length:** 25
* **OS NGD API – Features Filterable:** Yes
* **OS Select+Build Filterable:** Yes
* **Data Schema Version:** 2.0
  {% endtab %}

{% tab title="v1.0, v1.1" %}
This describes the methods of access normally utilised at the Site Access Location.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** false
* **Code List Name:** [accesstypevalue](https://docs.os.uk/osngd/code-lists/code-lists-overview/accesstypevalue)
* **Max Length:** 30
* **OS NGD API – Features Filterable:** Yes
* **OS Select+Build Filterable:** Yes
* **Data Schema Version:** 1.1
  {% endtab %}
  {% endtabs %}

### :new: access\_purpose

A description of the principal access function at the Site Access Location (for example, Private or Public).

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** true
* **Code List Name:**[ accesspurposevalue](https://docs.os.uk/osngd/code-lists/code-lists-overview/accesspurposevalue)
* **Max Length:** 15
* **OS NGD API – Features Filterable:** Yes
* **OS Select+Build Filterable:** Yes
* **Data Schema Version:** 2.0

### :new: access\_evidencedate (formerly accesstype\_evidencedate)

{% hint style="info" %}
This attribute was called `accesstype_evidencedate`  in data schema versions 1.0 and 1.1, and was renamed `access_evidencedate`  from version 2.0 onward.
{% endhint %}

{% tabs %}
{% tab title="2.0" %}
The date on which the latest evidence was gathered to make an update if required. For example, the date of collection by a surveyor or third party information received.

* **Data Types:** String (GeoJSON), Date (GPKG), Date (CSV)
* **Nullable:** true
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 2.0
  {% endtab %}

{% tab title="v1.0, v1.1" %}
The date the source of information for the update was provided. For example the date of imagery capture or the date of a field visit.

* **Data Types:** String (GeoJSON), Date (GPKG), Date (CSV)
* **Nullable:** true
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1
  {% endtab %}
  {% endtabs %}

### :new: access\_updatedate (formerly accesstype\_updatedate)

{% hint style="info" %}
This attribute was called `accesstype_updatedate`  in data schema versions 1.0 and 1.1, and was renamed `access_updatedate`  from version 2.0 onward.
{% endhint %}

Date when the attribute was last updated.

* **Data Types:** String (GeoJSON), Date (GPKG), Date (CSV)
* **Nullable:** false
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1, 2.0

### :new: accessedsiteid (formerly siteid)

{% hint style="info" %}
This attribute was called `siteid`  in data schema versions 1.0 and 1.1, and was renamed  `accessedsiteid`  from version 2.0 onward.
{% endhint %}

The unique identifier (OSID) of the site feature to which the SiteAccessLocation feature relates.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** false
* **Max Length:** 36
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1, 2.0

### routingpointid

The unique identifier (OSID) of the related Site Routing Point feature.

{% hint style="warning" %}
From 25 April 2023, this value has no longer been populated. As part of a data enhancement programme in late Spring 2023, all Site Routing Point features were recreated as [Road Nodes](https://docs.os.uk/osngd/data-structure/transport/transport-network/road-node) and therefore network references are now recorded and captured as [roadnodeid](#accessednetworknodeid-formerly-roadnodeid) in data schema versions 1.0 and 1.1 of Site Access Location.

See also [Site Routing Point](https://docs.os.uk/osngd/data-structure/land-use/land-use-features/site-routing-point) for more information.
{% endhint %}

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** true
* **Max Length:** 36
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1

### :new: accessednetworknodefeaturetype

The OS NGD network that the feature is accessed from (for example, Road Network).

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** true
* **Code List Name**: [networknodefeaturetypevalue](https://docs.os.uk/osngd/code-lists/code-lists-overview/networknodefeaturetypevalue)
* **Max Length:** 20
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 2.0

### :new: accessednetworknodeid (formerly roadnodeid)

{% hint style="info" %}
This attribute was called `roadnodeid`  in data schema versions 1.0 and 1.1, and was renamed  `accessednetworknodeid`  from version 2.0 onward.
{% endhint %}

{% tabs %}
{% tab title="2.0" %}
The unique identifier (OSID) of the network node that represents the point on that network that provides access to the Site Access Location feature.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** true
* **Max Length:** 36
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 2.0
  {% endtab %}

{% tab title="1.1 & 1.0" %}
The unique identifier (OSID) of the related RoadNode feature.

* **Data Types:** String (GeoJSON), String (GPKG), String (CSV)
* **Nullable:** true
* **Max Length:** 36
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 1.1
  {% endtab %}
  {% endtabs %}

### :new: distancetonetworknode\_m

The straight line measure between the accessednetworknodeid and the location of the access feature.

* **Data Types:** Number(GeoJSON), Float (GPKG), Real (CSV)
* **Nullable:** true
* **Precision:** 5
* **Scale:** 1
* **OS NGD API – Features Filterable:** No
* **OS Select+Build Filterable:** No
* **Data Schema Version:** 2.0