Users' Diaries

Recent diary entries

Greetings everyone! I have been active on OpenHistoricalMap since mid 2020 and have done a lot to contribute to the map. Countries in Europe are mapped extremely well and it is something nice to hear along with their corresponding borders. When it comes down to countries beyond Europe, East Asia and some parts of the Americas many more countries could be added to the map and I have added a few myself. In terms of where mapping could best be improved at is in Africa, Americas (beyond Canada and the US), Middle East and Oceania. If you set the slider to 2024 most of Africa, Middle East, Oceania, large parts of the Americas aren’t mapped that well.

Posted by jeffmeyer on January 21, 2024 in English (English).

New Stuff

Please be sure to check out:


More to come in 2024

This is from the Mapping USA 2024 OHM Office Hour notes:

  • Tighter integration with OSM US
  • Moar borders
  • Moar imports / linked data – Wikidata
  • Non-map data sources
  • Better documentation on wiki
  • Community / regional leaders
  • Better imagery support – ELI, etc.
  • Better editing support – RAPiD
  • Maplibre & mapstyle improvements
  • Local language labels
  • New logo?
  • Event support?

As someone who grew up in Newbury Park, California, I’ve always found the history of the area fascinating. Lately, I’ve gone through quite a bit of research to map out all of the original road alignments so that I might be able to picture what my homeland would have been like before the developers got ahold of it. As far as I can tell, the whole area was wide-open agriculture space.

Location: 34.157, -118.973
Posted by Natfoot on September 18, 2021 in English (English). Last updated on December 14, 2021.


I get distracted easily and have mapped thousands of prospects as a part of a mining area. This is not as well mapped in OSM as most of these are historic and don’t occur as new for OSM. They are still a hazard that presents in the current day. As such I got distracted mapping them,2021

Adits are also a less than ideally mapped location as they often show an entrance and a direction of travel into a hill on a TOPO map that we could be including that OSM does not allow for that detail.

9/20 added more prospects and springs from TOPO maps in the state of Nevada.,2021

Posted by Natfoot on August 17, 2021 in English (English).


Education Live Stream

User nfgusedautoparts live streamed: an OpenHistoricalMap talk - Extended Date Time Format Nfgusedautoparts live streams on Saturdays

User Natfoot (Me) also live streamed editing on OHM| Natfoot live streams on Mondays with a voice and video about Weekly OSM and Weekly OHM before editing on one of the platforms.

Posted by Cyberjuan on July 4, 2021 in English (English). Last updated on August 7, 2021.

Tawantinsuyo was the Quechua name for the Inca Empire, the pre-Columbian empire that ruled present Peru, Bolivia, Ecuador and parts of Colombia, Argentina and Chile, before the Spanish arrived to America.

A free interactive historical map it’s something hard to find in Peru, so a young engineer made the first map of this kind for the Inca Empire. I interviewed him to find out his motivations and goals with this project. Apart from that I talked with an archaeologist friend to know about his views on the potential of this kind of maps for historians and other academics.

I would post the whole article here but it is a bit too long, so I am copying the first three parragraphs and then putting the link to the Medium post, you can read it complete there. Thanks!

Mapping the Tawantinsuyo in OpenHistoricalMap

A few days ago I found about the existence of a platform called OpenHistoricalMap and that someone there had made a Tawantinsuyo map. Given my interest in historical issues, especially if they are related to the Inca Empire, I decided to contact whoever had this interesting idea.

That was how I virtually met Rubén López, a young systems engineer, graduated from the University of Huamanga, who works -like other local people- in Development Seed, a global company that provides geospatial solutions and has an office in Ayacucho, Peru, and where this Peruvian team develops map applications.

One of the projects they support is precisely OpenHistoricalMap, and Rubén sees the part of server architecture through docker and kubernetes technologies in AWS. The project is similar to OpenStreetMap, with the difference that OpenHistoricalMap stores historical data. This data is accessible with a free license for its use, that is, any person or organization can use this data for jobs, websites or others.

Please continue reading by clicking here

Location: -12.046, -77.031

Kiwirail Networks opened the deviation of the Main North Line between 262 and 263 km (Tunnel 21) and announced it on the 2021-05-25 on their website. A way has been added to OHM showing the closed section of track.

I’m new to OHM but have extensive experience drawing my own maps in a GIS so this is the first edit I have made to OHM.

so something has gone away in the real world, and rather than just deleting it from OpenStreetMap, you’d like to move it to OpenHistoricalMap.

That’s a great idea, but don’t rush.

OHM and OSM have different licensing philosophies. The entirety of the OSM database is licensed under the ODbL and content in the database is licensed under the Database Contents License.

OHM has a mixed licensing philosophy. The license tag should be set on entities in the DB (high level relations or ways, no need to tag everything). Using CC0 (about the same as Public Domain) is preferred. Somethings may be licensed CC-BY-SA.

Because of this, there are steps you need to take.

First you need to examine the history of the object and find out who edited it (could be more than one person). Sometimes you’re fortunate and there is only one editor, which makes it easier. You will need to reach out to them, probably using the OSM messaging system, to find out if they object to their work being moved. Be respectful and nice, and explain clearly what you are doing. Emphasize that yorr goal is to preserve their work. Explain that it will need to be relicensed, preferably under CC0 (failing that, CC-BY-SA). You will find that many (most?) mappers are happy with this and will grant permission.

You will then need to hone your map editor skills, exporting the .osm file from OSM and importing it to OHM. Do not forget to add the extra OHM tags - license, source, start & end dates. Make sure you give credit.

Some things may be approached differently. For example, you may find that something predates the license change. In this case, it may well be available from the planet at If, for example, it is unmodified TIGER then it was originally public domain and is up for grabs. But if it’s unmodified TIGER, there is a fair chance an improved copy exists on the Census Bureau website so consider sourcing it there.

First in a series about ways to find imagery.


Old Maps Online is not so much a source, as a map enabled directory for maps. You go there, find the place you want using the map, and look at the panel on the right side of the browser for old maps.

None of these maps are hosted on Old Maps Online. They are in various repositories world wide. This makes it important to check copyright and licenses for the sites before using the imagery.

Some may have URLs that are usable in JOSM or iD already. Others simply have a way to retreive the map. In the later case you can use [] - see my diary entry with links to a number of youtube videos on Map Warper.

Posted by nfgusedautoparts on July 7, 2020 in English (English).

i put together a couple of things on youtube showing various scenarios for using mapwarper. for folks new to OHM who want to know how to bring in source material that isn’t already geo referenced, this should help a bit.

1) In this one, i take a 1834 survey map of the Albany terminus of the Erie Canal, load it into mapwarper, rectify it, and then bring it into JOSM for editing:


2) In this one, i take an aerial image from 1952 which in theory contains the footprint of Clearview Speedway in South Westerlo NY (from USGS earthexplorer), bring it into mapwarper and align it. the scenario is a little different from the survey map, the image is much larger and a few issues show up that need to be addressed:


3) In this one, I look at what can be done to deal with the case where there is more than one map on a single scanned image, in this case something already scanned in on the NYPL website, but not quite usable as is:


Greetings from the cloud! (and SF, CA, USA, NA, Earth)

Lots going on here at OHM and we’re very excited about it all. Please take a look through the items below and let us know if you have any questions. As always, we’re looking for help from interested parties in organizing and managing this effort. Ping us on the maillist (, OSM-US Slack #openhistoricalmap, OSM World Discord #openhistoricalmap.

OSM-US Mappy Hour - 8 Jul, 8:30pm ET

July 8, 8:30pm ET, 5:30pm PT Richard Welty will be leading This will be a great time for new users to get up to speed and to see who else in the community is interested in historical mapping. It’s a great way to get connected to OSM-US, as well. It’s a great group.

TeachOSM - July, tbd

Steven Johnson, the coordinator of TeachOSM is a huge proponent of OHM and has put together some instructional tasks for OHM using the TeachOSM tasking manager. We’ve talked about having a combined event in July, but have not nailed down the date and time yet. He’s already posted some cool OHM tasks here: (this reminds me… we need to get the OHM tasking manager back up!)

New videos

Richard Welty is doing all the heavy lifting these days - he just posted a couple of how-to videos. First one: Second one: These are very well-paced, easy to understand, but certainly not slow. Richard covers a lot of ground with some great examples.


Just a reminder, the following tags are highly encouraged for your ways & relations:
* start_date = YYYY-MM-DD
* end_date = YYYY-MM-DD
Without one of these tags in that exact format, OHM will not render those ways or relations properly. iD has a form entry that makes it easy for you - it doesn’t look like it uses YYYY-MM-DD, but it does.

Other encouraged tags are: * source = [url of your source map] * wikipedia:en = [article name without spaces] * wikidata = [wikidata Q code]

I expect the discussion around tagging formats and standards to pick up quite a bit in the next few weeks, so please stay tuned.


We’ve been very focused on getting the dev environment squared away (see below), and haven’t made as much progress as we would have liked. This all relates to how we’re going to organize this community, plan activities, run website development, etc. If you’ve ever wanted to get involved in an open source project and you love old maps… well, hello!

Site Content Updates & Copyright Statements

We’re in the middle of scrubbing all of our site’s content, to remove references to OSM, where appropriate, and update all of our copyright statements. What is there now is a first-draft replacement of the OSM policy. Please take a look at it if you’re interested & let us know your thoughts.

Dev Environment

The dev environment is close to getting stabilized. What this means is: * Most of the migration-related bugs have been resolved. You should be able to use the site without repeatedly logging in, most of the internal links should be pointing in the right places (most, but not all… we’re working on those)
* The code base is getting stabilized into production, staging, and feature branches. Updates will be made to staging via PRs and once tested there, changes can be deployed to production. For those into these sorts of things… this is a big deal for us. Huge. Very exciting.
* It’ll be much clearer how volunteers can help contribute to the project.
* We’ll have a more detailed description of everything published in the not-too-distant future.

Future work

Development work for the site will continue even after things stabilize. (or, because things stabilize, dev work will be even easier & faster!). Targeted improvements in the near term include:
* Stylesheet updates
* Enhanced inspector / query features function
* Large area imports

Please keep the questions coming & spread the word. Follow @openhistmap on Twitter!

Location: 0.000, 0.000
Posted by jeffmeyer on May 17, 2020 in English (English).

Hi everybody -

We’re back online, but working through quite a laundry list of items to fix.

Please bear with us as we hammer through them: - Slow rendering of edits - it may take a while (a long while) for your edits to show up on the site. - Timeslider issues. These may be related to the prior item. - Logging users out - sessions may be cut short or the site may forget you are you. - Nominatim is working, kind of… some of the links may not work properly.

As always, your patience is very much appreciated & the dev team is working as fast as it can to resolve everything.

Now, for the good news… what is working: - Saving edits - you can work offline and upload your edits to the site.

Stay tuned… more updates on the way, Best wishes & keep on mappin’! Jeff

Location: 37.827, -122.423

A power shutdown of the machine room for pre-semester maintenance will occur tomorrow. The length of the shutdown should be less than the window and services will return gradually afterwards. Overpass API may be slower due to processing issues.

Please see

Posted by NitaRae on May 11, 2019 in English (English).

Most of the survey map I am working from were generated between 1825 and 1855. These are the result of a 30 year effort to produce an accurate and reasonably complete set of surveys for the territory/state of Florida. Survey’s were conducted in the field by a 4 or 5 man crew consisting of a Deputy Surveyor, two chain-men, and an ax-man. These were rugged and inhospitable virgin woods. The crew was paid $4-$6 mile to do the field work. Payment computations are on the margins of the plat sheets.

Surveyors working in the field were required to leave physical indicators of township, range and section corners. They may have been an iron pipe, and a heavy wooden stake. Because of the high probability that the survey markers would be disturbed, or degraded with time, trees in the immediate area of the corner were designated witness trees. Their exact position relative to the corner was documented and recorded in the field notes. The witness trees were usually marked with a cat-face, or chevrons, to positively identify them. Some of those marked trees survived beyond 100 years of age, and a rare few made it to 200 years. One tree, was documented as germinating several years before the constitution was signed. It was inadvertently cut down around 1981.

The initial result of the field surveys was a hand written note book, giving dates, measurements, compass headings, etc. This information was being calculated in the field using basic equipment, which was state of the art for the day. The completed field notebooks were returned to the land office responsible for that part of the state. There, the numbers would be verified, and a drafts-person would generate a visual survey document. That would have to be rechecked for errors, before being approved by the surveyor general, or one of his deputies.

Comparison of the finished sheets, to current USGS topographical maps, suggests that the drafts-persons may have used a wee bit of literary license with some of the drawings. The features may well have existed, but their placement might not always be spot on. So beware,