> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-apis/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-apis/accessing-os-apis/os-maps-api/getting-started/arcgis-online.md).

# ESRI ArcGIS Online

Accessing OS Maps API via ESRI ArcGIS Online

ArcGIS Online is a geographic information system (GIS) delivered using the software-as-a-service (SaaS) model. ArcGIS Online services are managed by ESRI and accessed by a client running on a wide range of options.

## What you need

* OS Maps API added to an API project in the OS Data Hub with an API Key; see [Getting started with an API project](/os-apis/core-concepts/getting-started-with-an-api-project.md) for more information
* An ArcGIS Online account

## Instructions

{% stepper %}
{% step %}

#### Add a new layer

Once you've signed into your ESRI ArcGIS Online account and opened the map viewer.

* Select *Layers* > *Add* > *Add layer from URL*.

<figure><img src="https://content.gitbook.com/content/oEzqrBzRGoJw7nQyLj1W/blobs/pdJoHw8pXZg2XKcr4LJK/image" alt="ArcGIS Online Layers dialog." width="316"><figcaption><p>ArcGIS Online Layers dialog.</p></figcaption></figure>
{% endstep %}

{% step %}

#### Add an API and set up custom parameters

In the Add Layer dialog:

* **URL**: Enter the base URL for OS Maps API, excluding the API Key. For example, <https://api.os.uk/maps/raster/v1/wmts>
* **Type**: Select *WMTS (OGC)*.
* Select *Custom request parameters* and enter the following:
  * **Parameter**: key
  * **Value**: \[Insert your OS API Key here]
* Click *Next*.

<figure><img src="https://4043944746-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FoEzqrBzRGoJw7nQyLj1W%2Fuploads%2Fgit-blob-b64485dd5808f17ce97b28be08dde401ab1600e6%2FWMTS%20Add%20Layer.png?alt=media" alt="ESRI ArcGIS Pro Add WMTS (OGC) Server Connection dialog with URL and custom request parameters set."><figcaption><p>ESRI ArcGIS Pro Add WMTS (OGC) Server Connection dialog with URL and custom request parameters set.</p></figcaption></figure>
{% endstep %}

{% step %}

#### Adding layers to the map

In the Add Layer dialog:

* Select a layer to add to the map
* Set the max feature limit
* Click *Add to map*.

<figure><img src="https://4043944746-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FoEzqrBzRGoJw7nQyLj1W%2Fuploads%2Fgit-blob-78786ac77c95d815eae17f9342866c488dbe8241%2FWMTS%20Add%20Layer%20style.png?alt=media" alt="ArcGIS Online Add Layers dialog: Select a layer to add to map."><figcaption><p>ArcGIS Online Add Layers dialog: Select a layer to add to map.</p></figcaption></figure>

\_The layer will then display in the Layers panel and the data will display on the map:

<figure><img src="https://4043944746-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FoEzqrBzRGoJw7nQyLj1W%2Fuploads%2Fgit-blob-bc782f42eefed7b9476c3e36bee8b9edbdf0238b%2FWMTS%20Map%20Added.png?alt=media" alt="ArcGIS Online UI showing OS Maps API in the map area."><figcaption><p>ArcGIS Online UI showing OS Maps API in the map area.</p></figcaption></figure>
{% endstep %}
{% endstepper %}


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.os.uk/os-apis/accessing-os-apis/os-maps-api/getting-started/arcgis-online.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.