OpenHistoricalMap/Reuse
As an open data project, OpenHistoricalMap encourages you to reuse the data in your own research and creative projects.
Vector tiles and stylesheets
You can embed an OpenHistoricalMap-based map on your website or in your native application using either Mapbox GL or MapLibre. If you need to use Leaflet, install the Mapbox GL Leaflet or MapLibre GL Leaflet plugin.
The stylesheets on the OpenHistoricalMap website conform to the Mapbox Style Specification and MapLibre Style Specification, so you can set your map to one of these styles directly:
Or if you prefer to write your own style, you can point it to OpenHistoricalMap vector tiles using the following URL template:
https://vtiles.openhistoricalmap.org/maps/osm/{z}/{x}/{y}.pbf
The layout of each vector tile is defined in a series of TOML files. You can inspect the tiles' contents using this Tegola inspector.
Whether you use an existing style or create your own, you will need to filter the features by the start_decdate and end_decdate properties, which correspond to the start_date=* and end_date=* tags converted to decimal years. The ohm-embed-1yr project demonstrates this filtering in a simple map powered by MapLibre GL JS. For Leaflet-based maps, the OpenHistoricalMap Timeslider plugin handles the filtering step and provides a friendly user interface for adjusting the year to filter by.
Please credit OpenHistoricalMap contributors on or near the map. You can easily provide attribution by setting the customAttribution option when initializing the Mapbox or MapLibre map object.
Querying the data
Overpass
- Main article: OpenHistoricalMap/Overpass
OpenHistoricalMap's Overpass API instance allows you to query the database for elements matching very specific criteria. For example, you could search for trees that were planted in a certain city during a particular date range near a certain kind of building – all subject to whether these details have been mapped, of course. You can query OpenHistoricalMap's Overpass API instance directly over HTTPS or using Overpass turbo or Overpass Ultra within a Web browser.
QLever
- Main article: OpenHistoricalMap/QLever
QLever provides an endpoint for rapidly querying the global OpenHistoricalMap dataset. As with the Overpass API, you can query for arbitrary, specific criteria; however, you use the standard query language SPARQL. SPARQL queries can federate with a number of other datasets, including OpenStreetMap and Wikidata. QLever can display results as a table, map, or heatmap.
Nominatim
OpenHistoricalMap's Nominatim instance lets you search for features by name or a limited selection of other search terms. The API endpoint is located at:
https://nominatim-api.openhistoricalmap.org/
A Web interface provides extra information that can be useful in diagnosing unexpected results.
Planet
For high-volume data processing, the entire contents of the OpenHistoricalMap database are available in planet.osm format on Amazon s3. Browse the available planet files. A new planet file containing the current database contents is generated daily. A more complete planet file, containing the database's full revision history, is generated weekly. The revision history allows you to track changes in the database over time, not to be confused with real-world changes over time.
If you do not need all the data about every place in all of history, consider extracting a part of the database using Overpass or the REST API. We do not have a regional extract service at the moment, but please let us know if you are able to provide such a service.
REST API
OpenHistoricalMap's main REST API allows you to upload and download raw data in OSM XML format. This is generally only useful to developers of OpenHistoricalMap software. However, if you have a node, way, or relation ID and simply need to look up its raw tags, this would be the fastest and most up-to-date method. The API endpoint is located at:
https://www.openhistoricalmap.org/api/0.6/
Legal considerations
In general, OpenHistoricalMap data is in the public domain under a CC0 dedication. As a courtesy, please credit OpenHistoricalMap contributors where appropriate. Some individual features may have additional legal requirements around attribution, as detailed in Open Historical Map/Copyright and Open Historical Map/OHM Contributors.
Examples
For inspiration, here are some examples of mashups that incorporate OpenHistoricalMap data:
- Richard Welty's Ghost Tracks prototype
- Leaflet widget
- Mapy židovského osídlení 1857–1930 – interactive map of the historic Jewish populations of several Czech towns by Daniel Baránek
- Mashup of OpenStreetMap (Shortbread) vector tiles and historic railways from OpenHistoricalMap