Open Historical Map
Open Historical Map (OHM) (http://www.openhistoricalmap.org) is an effort to use the OSM infrastructure as a foundation for creating the world's most universal, detailed, and out-of-date map. OHM will focus on the mapping elements where OSM excels - shores, political boundaries, buildings, and ways. Future and other efforts may engage in discussing actions, events, people, and movable items.
Note: As opposed to other projects such as OpenSeaMap, OHM makes use of its own database independent of OSM.
An early draft Open Historical Map/FAQ is available.
|openhistoricalmap.org website is offline due to a server disk problem.
"Current status is we've backed everything up and waiting for people with time and knowledge to resurrect the various components."  
List of Open Historical Map/Projects.
OpenHistoricalMap data can be edited online using both iD and Potlatch. The iD editor is embedded within the OHM website.
Using JOSM it is necessary to alter the api connection parameter (uncheck the default): use http://www.openhistoricalmap.org/api/ (note http not https as on the OSM site).
How to map
Apply a start date and/or end date to the feature. The format is ISO 8601 format YYYY-MM-DD
If you don't know the actual day, you can just add the year start_date=1925
- before 1910-01-20 (before a specific date - possibly when a photo was taken)
- 1900..1925 (between 1900 and 1925)
Tracing from Imagery
JOSM - works with WMS Server, Tile Servers and local images. See JOSM Imagery Guide for more information.
iD Editor - open the layers panel, click "Custom" and paste in a valid Tile URL template
Google Summer of Code Proposal
A number of projects that are in the Wikimaps, OSM, OHM, Wikimedia area would benefit from the temporal flexibility in the OSM tool stack. This would allow us to use data across projects, using layers from multiple sources at different time periods. These projects include:
- design a how-to map
- Enhance iD and The Rails Port so that meta-data hooks are added to the code that allow for custom deployments of both software. The intent is to support their use as dedicated user interfaces to certain applications (such as medieval walking path editing) while still using a generic data source.
Using the data
There are a variety of ways to use OpenHistoricalMap Data.
For smallish scale it is possible to download data using JOSM. Two alternatives now exist for larger volumes of data or larger areas:
- A weekly OHM planet file (see http://planet.openhistoricalmap.org/)
- A special Overpass instance at http://overpass.openhistoricalmap.org/.
- OHM/Copyright - to start documenting copyright-related issues for OHM
- OHM/Dev - get The Rails Port, Mapnik, Mod tile, and Nominatim up and running at http://www.openhistoricalmap.org
- OHM/TileServer - Tile serving discussion and docs.
- OHM/Tags - identify OHM tagging conventions
- OHM/Plan - longer-term plans
Related OSM Projects
- OSM-4D (see German version -translation link on top- as English version needs more translation)
- Historic - OSM Wiki page on Historic sites in general
- Proposed_features/historic_event - Failed proposal for including events in the OSM database
- Historic Objekts - An atlas of historic sites based on OSM
- HistOSM - An atlas of historic sites based on OSM, out of the University of Heidelberg
- HistOSM.org Paper - paper by Michael Auer and Alexander Zipf
- Open Historical Map maillist: http://lists.openstreetmap.org/listinfo/historic
- Open Historical Map irc: #ohm on irc.oftc.net
- Group on Facebook: https://www.facebook.com/groups/1513784935591521/
- Tech Changes to the OpenStreetMap Stack, Tim Waters, SotM 2015
- City Stripping: building historical road layouts from todays data, Maps Matter blog post, 11 Dec 2014
- Curating a Historical Map, Living With Dragons blog post, 21 July 2014
- Wikimaps Expeditions, Susanna Anas video presentation, SotM 2014
- Historical maps, Jerry Clough video presentation, SotM 2014
- Open Historical Map reusing obsolete information, David Evans, SotM 2013
- Summary of Hangout December 2012
- OSM & Online Time Machines, Jeff Meyer, SotM 2012
- Mapping History on Open Street Map, Frankie Roberto, SotM 2009