# Valhalla

> Open Source Routing Engine for OpenStreetMap

**Wikidata**: [Q122264835](https://www.wikidata.org/wiki/Q122264835)  
**Source**: https://4ort.xyz/entity/valhalla

## Summary
Valhalla is an open-source routing engine designed specifically for use with the OpenStreetMap (OSM) database. It operates as a freely accessible software tool, allowing users to utilize and redistribute the code under the permissive MIT License. The project is recognized as a Mapzen project and is maintained by GIS OPS and Mapzen.

## Key Facts
- **Classification:** Valhalla is an instance of open-source software and an OpenStreetMap routing tool.
- **License:** The engine is distributed under the MIT License.
- **Base Data:** It is built upon and utilizes the OpenStreetMap database.
- **Maintainers:** The project is maintained by GIS OPS and Mapzen.
- **Authors:** Key authors and contributors include David Nesbitt, Kevin Kreiser, Greg Knisely, and Duane Gearhart.
- **Repository:** The source code is hosted on GitHub at `https://github.com/valhalla/valhalla`.
- **Documentation:** Detailed documentation is available in English at `https://valhalla.readthedocs.io`.
- **Version History:** The software has recorded stable releases dating from February 2017 (Version 2.0.9) through July 2017 (Version 2.3.0).
- **Project Status:** It is listed in the OSM Apps Catalog and described by the OpenStreetMap Wiki.

## FAQs
### Q: What is the primary function of Valhalla?
A: Valhalla functions as an open-source routing engine. It calculates routes and provides navigation logic specifically using data from the OpenStreetMap project.

### Q: Under what license is Valhalla distributed?
A: Valhalla is distributed under the MIT License. This allows users to freely use, redistribute, and access the source code.

### Q: Who developed and maintains Valhalla?
A: Valhalla was authored by David Nesbitt, Kevin Kreiser, Greg Knisely, and Duane Gearhart. It is currently maintained by GIS OPS and Mapzen.

### Q: Where can the source code for Valhalla be found?
A: The source code repository is located on GitHub under the username `valhalla`.

## Why It Matters
Valhalla represents a significant contribution to the geospatial software ecosystem by providing a robust, open-source routing engine specifically optimized for OpenStreetMap data. In a field often dominated by proprietary "black box" solutions, Valhalla offers transparency and flexibility, allowing developers to integrate sophisticated routing capabilities into their applications without licensing fees or restrictions typically associated with commercial software.

As a project associated with Mapzen, it played a role in the wave of open geo-tooling that aimed to make high-quality mapping accessible to a broader audience. Its inclusion in the OSM Apps Catalog underscores its relevance to the OpenStreetMap community. By offering a permissive MIT License, Valhalla empowers organizations to customize routing algorithms to fit specific needs—such as multimodal transport or custom costing models—while ensuring the software remains libre and accessible for future development.

## Notable For
- **Open Source Routing:** Distinguished as a dedicated routing engine for OpenStreetMap that is completely open source.
- **Permissive Licensing:** Utilizes the MIT License, offering broader freedom for modification and redistribution compared to stricter copyleft licenses.
- **Mapzen Heritage:** Notable for its origins and association with Mapzen, a prominent player in the open mapping landscape.
- **Active Development:** Features a history of frequent updates, with multiple stable versions released throughout 2017.
- **Community Integration:** Fully integrated into the OpenStreetMap ecosystem, cataloged within the OSM Apps Catalog.

## Body
### Technical Identity
Valhalla is defined as an OpenStreetMap routing tool and a piece of open-source software. It is engineered to process OpenStreetMap database files to generate routes. The software is copyrighted but freely available under the MIT License, ensuring that the original source code is accessible to the public.

### Project History and Management
The project is classified as a Mapzen project. It was authored by a team comprising David Nesbitt, Kevin Kreiser, Greg Knisely, and Duane Gearhart. Ongoing maintenance is managed by GIS OPS and Mapzen. The project is documented on the OpenStreetMap Wiki and listed in the OSM Apps Catalog.

### Version Timeline
According to structured data retrieved in September 2023, Valhalla has a recorded history of stable releases primarily concentrated in the first half of 2017:
- **2.0.9:** Released 2017-02-17
- **2.1.7:** Released 2017-03-28
- **2.2.0:** Released 2017-05-08
- **2.2.8:** Released 2017-06-23
- **2.3.0:** Released 2017-07-10 (The latest version listed in the provided source material).

### Resources and Access
The project's source code is accessible via its GitHub repository (`https://github.com/valhalla/valhalla`). For developers and users, English-language documentation is hosted at `https://valhalla.readthedocs.io/en/latest/` and `https://valhalla.readthedocs.io`.

## References

1. [Source](https://www.mapzen.com/blog/valhalla-intro/)
2. [Release 2.0.9. 2017](https://github.com/valhalla/valhalla/releases/tag/2.0.9)
3. [Release 2.1.7. 2017](https://github.com/valhalla/valhalla/releases/tag/2.1.7)
4. [Release 2.2.0. 2017](https://github.com/valhalla/valhalla/releases/tag/2.2.0)
5. [Release 2.2.3. 2017](https://github.com/valhalla/valhalla/releases/tag/2.2.3)
6. [Release 2.2.4. 2017](https://github.com/valhalla/valhalla/releases/tag/2.2.4)
7. [Release 2.2.5. 2017](https://github.com/valhalla/valhalla/releases/tag/2.2.5)
8. [Release 2.2.6. 2017](https://github.com/valhalla/valhalla/releases/tag/2.2.6)
9. [Release 2.2.8. 2017](https://github.com/valhalla/valhalla/releases/tag/2.2.8)
10. [Release 2.2.9. 2017](https://github.com/valhalla/valhalla/releases/tag/2.2.9)
11. [Release 2.3.0. 2017](https://github.com/valhalla/valhalla/releases/tag/2.3.0)
12. [Release 2.3.2. 2017](https://github.com/valhalla/valhalla/releases/tag/2.3.2)
13. [Release 2.3.3. 2017](https://github.com/valhalla/valhalla/releases/tag/2.3.3)
14. [Release 2.3.4. 2017](https://github.com/valhalla/valhalla/releases/tag/2.3.4)
15. [Release 2.3.5. 2017](https://github.com/valhalla/valhalla/releases/tag/2.3.5)
16. [Release 2.3.6. 2017](https://github.com/valhalla/valhalla/releases/tag/2.3.6)
17. [Release 2.3.7. 2017](https://github.com/valhalla/valhalla/releases/tag/2.3.7)
18. [Release 2.3.8. 2017](https://github.com/valhalla/valhalla/releases/tag/2.3.8)
19. [Release 2.3.9. 2017](https://github.com/valhalla/valhalla/releases/tag/2.3.9)
20. [Release 2.4.0. 2017](https://github.com/valhalla/valhalla/releases/tag/2.4.0)
21. [Release 2.4.1. 2017](https://github.com/valhalla/valhalla/releases/tag/2.4.1)
22. [Release 2.4.3. 2017](https://github.com/valhalla/valhalla/releases/tag/2.4.3)
23. [Release 2.4.4. 2018](https://github.com/valhalla/valhalla/releases/tag/2.4.4)
24. [Release 2.4.5. 2018](https://github.com/valhalla/valhalla/releases/tag/2.4.5)
25. [Release 2.4.6. 2018](https://github.com/valhalla/valhalla/releases/tag/2.4.6)
26. [Release 2.4.7. 2018](https://github.com/valhalla/valhalla/releases/tag/2.4.7)
27. [Release 2.4.8. 2018](https://github.com/valhalla/valhalla/releases/tag/2.4.8)
28. [Release 2.4.9. 2018](https://github.com/valhalla/valhalla/releases/tag/2.4.9)
29. [Release 2.5.0. 2018](https://github.com/valhalla/valhalla/releases/tag/2.5.0)
30. [Release 2.6.0. 2018](https://github.com/valhalla/valhalla/releases/tag/2.6.0)
31. [Release 2.6.1. 2018](https://github.com/valhalla/valhalla/releases/tag/2.6.1)
32. [Release 2.6.2. 2018](https://github.com/valhalla/valhalla/releases/tag/2.6.2)
33. [Release 2.6.3. 2018](https://github.com/valhalla/valhalla/releases/tag/2.6.3)
34. [Release 2.7.0. 2018](https://github.com/valhalla/valhalla/releases/tag/2.7.0)
35. [Release 2.7.1. 2018](https://github.com/valhalla/valhalla/releases/tag/2.7.1)
36. [Release 2.7.2. 2018](https://github.com/valhalla/valhalla/releases/tag/2.7.2)
37. [Release 3.0.0. 2018](https://github.com/valhalla/valhalla/releases/tag/3.0.0)
38. [Release 3.0.1. 2018](https://github.com/valhalla/valhalla/releases/tag/3.0.1)
39. [Release 3.0.2. 2019](https://github.com/valhalla/valhalla/releases/tag/3.0.2)
40. [Release 3.0.3. 2019](https://github.com/valhalla/valhalla/releases/tag/3.0.3)
41. [Release 3.0.4. 2019](https://github.com/valhalla/valhalla/releases/tag/3.0.4)
42. [Release 3.0.5. 2019](https://github.com/valhalla/valhalla/releases/tag/3.0.5)
43. [Release 3.0.6. 2019](https://github.com/valhalla/valhalla/releases/tag/3.0.6)
44. [Release 3.0.7. 2019](https://github.com/valhalla/valhalla/releases/tag/3.0.7)
45. [Release 3.0.8. 2019](https://github.com/valhalla/valhalla/releases/tag/3.0.8)
46. [Release 3.0.9. 2019](https://github.com/valhalla/valhalla/releases/tag/3.0.9)
47. [Release 3.1.0. 2021](https://github.com/valhalla/valhalla/releases/tag/3.1.0)
48. [Release 3.1.1. 2021](https://github.com/valhalla/valhalla/releases/tag/3.1.1)
49. [Release 3.1.2. 2021](https://github.com/valhalla/valhalla/releases/tag/3.1.2)
50. [Release 3.1.3. 2021](https://github.com/valhalla/valhalla/releases/tag/3.1.3)