# Page Not Found

The URL `deep-dive/a-guide-to-coordinate-systems-in-great-britain/converting-between-3d-cartesian-and-ellipsoidal-latitude-longitude-and-height-coordinates` does not exist. This page may have been moved, renamed, or deleted.

## Suggested Pages

You may be looking for one of the following:
- [Converting between 3D Cartesian and ellipsoidal latitude, longitude and height coordinates](https://docs.os.uk/more-than-maps/a-guide-to-coordinate-systems-in-great-britain/converting-between-3d-cartesian-and-ellipsoidal-latitude-longitude-and-height-coordinates.md)
- [Converting between grid eastings and northings and ellipsoidal latitude and longitude](https://docs.os.uk/more-than-maps/a-guide-to-coordinate-systems-in-great-britain/converting-between-grid-eastings-and-northings-and-ellipsoidal-latitude-and-longitude.md)
- [National Grid and the OSGB36 TRF](https://docs.os.uk/more-than-maps/a-guide-to-coordinate-systems-in-great-britain/ordnance-survey-coordinate-systems/national-grid-and-the-osgb36-trf.md)
- [The International Terrestrial Reference Frame (ITRF)](https://docs.os.uk/more-than-maps/a-guide-to-coordinate-systems-in-great-britain/modern-gnss-coordinate-systems/the-international-terrestrial-reference-frame-itrf.md)
- [The International GNSS Service (IGS)](https://docs.os.uk/more-than-maps/a-guide-to-coordinate-systems-in-great-britain/modern-gnss-coordinate-systems/the-international-gnss-service-igs.md)

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Perform an HTTP GET request on the documentation index with the `ask` parameter:

```
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```

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### Option 2 — Browse the documentation index

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### Option 3 — Retrieve the full documentation corpus

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Use this to access all content at once and perform your own parsing or retrieval. It will be more expensive.

## Tips for requesting documentation

Prefer `.md` URLs for structured content, append `.md` to URLs (e.g., `/more-than-maps/a-guide-to-coordinate-systems-in-great-britain/converting-between-3d-cartesian-and-ellipsoidal-latitude-longitude-and-height-coordinates.md`).

You may also use `Accept: text/markdown` header for content negotiation.