> 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/cadcorp-sis.md).

# Cadcorp SIS

Accessing OS Maps API via Cadcorp SIS

The Cadcorp Spatial Information System® (Cadcorp SIS®) is an integrated family of geospatial products comprising desktop, web, and developer applications.

Cadcorp SIS Desktop connects directly to the Ordnance Survey Data Hub through dedicated wizards.

## 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
* Cadcorp SIS version SIS 9 or later

{% hint style="info" %}
**Note**: We used Cadcorp version 9.1.1668 to create these instructions.
{% endhint %}

## Instructions

{% stepper %}
{% step %}

#### Add overlay

Once a new map has been set up, in the Home tab, click *Add Overlay*.

<figure><img src="https://4043944746-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FoEzqrBzRGoJw7nQyLj1W%2Fuploads%2Fgit-blob-ecdf1602850c1efa07580e28e94a54d61312150c%2Fimage.png?alt=media" alt="Cadcorp SIS Desktop UI showing Home > Add Overlay navigation option"><figcaption><p>Cadcorp SIS Desktop UI showing Home > Add Overlay navigation option</p></figcaption></figure>
{% endstep %}

{% step %}

#### Select API

In the Overlay Types dialog:

* Select *Ordnance Survey (GB) > OS (GB) Data Hub*, and then click *Next*.

In the OS (GB) Data Hub dialog:

* Select \_OS Maps API.
* **API Key**: Enter your API key (If you **do not have** an API key this can be left blank but will r*estrict your access to free open data*).
* **Premium/Public Sector Plan**: Select this option if you have this plan.
* **Save in the UI settings database (encrypted)**: Select this option.
* Click *Next*.

<figure><img src="https://4043944746-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FoEzqrBzRGoJw7nQyLj1W%2Fuploads%2Fgit-blob-ef8549eae7a3c71bf952ae708ceb82ec9a6fb6a0%2FMaps-Cadcorp-6.png?alt=media" alt="Cadcorp SIS Desktop  OS (GB) Data Hub dialog"><figcaption></figcaption></figure>
{% endstep %}

{% step %}

#### Adding layers to the map

In the OS (GB) Data Hub Maps API Layers dialog, select your preferred layer, and then click *Finish* to save the information and close the dialog.

<figure><img src="https://4043944746-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FoEzqrBzRGoJw7nQyLj1W%2Fuploads%2Fgit-blob-34fbadd8c50a7b9ef4a4bfce1b9c86cb12f9a52e%2FMaps-Cadcorp-7.png?alt=media" alt="Cadcorp SIS Desktop OS (GB) Data Hub Maps API Layers dialog"><figcaption></figcaption></figure>

*The selected layer will then display in the* SIS Workspace Definition (SWD) \_and the data will display in the map area:

<figure><img src="https://4043944746-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FoEzqrBzRGoJw7nQyLj1W%2Fuploads%2Fgit-blob-81c44bfb1f7cac17d6812614b13f8d880a02a966%2FMaps-Cadcorp-8.png?alt=media" alt="Cadcorp SIS Desktop UI showing OS Maps API data in the map area"><figcaption></figcaption></figure>
{% endstep %}
{% endstepper %}


---

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