Many people mistakenly assume OpenHistoricalMap is a brand-new project. In fact, we’ve been around much longer than our youthful, experimental ethos would suggest. This week, we’re celebrating 15 years, just days before our big sibling, OpenStreetMap, celebrates its 20th birthday.
As is frighteningly common in the field of historical GIS, various sources give conflicting dates as to when this project was established. The earliest date is July 30, 2009, at 19:21:10 UTC, when someone registered the openhistoricalmap.org domain name, according to WHOIS. In geographical terms, this is the equivalent of establishing a landuse=greenfield and sticking a “Coming Soon” sign in the ground.
The most commonly cited start date is April 14, 2013, when the first version of the site went live. The Wayback Machine’s earliest snapshots of the site aren’t much to look at. Unfortunately, slippy maps are the biggest unarchived gap in Internet history. 
We have more cause to celebrate the July 2018 launch of a vector tile server, which gave OHM bragging rights for adopting this important technology six years before OSM (and counting). But the euphoria over this launch only makes sense in the context of a catastrophic dataloss incident in 2017, followed by the site going down. @batpad was there; he tells this story much better than I can:
And then, on July 31, 2019, we finally introduced a time slider, demonstrating the importance of adopting vector tiles a year earlier. One scrub of that slider, and nothing that came before really mattered anymore in the grand scheme of things.
These ups and downs are important to recount, but as the chronologies of our dated element and building coverage over time make abundantly clear, the technology milestones are just footnotes on our path to mapping world history. The real story is what we’re doing with the technology, how we’re using it to inform and inspire people about the past and present.
Many people were involved in OHM in the early days, well before my time. You may recognize some of their names, while others have moved on from the project. We’re also standing on the shoulders of countless individuals in the OSM project and its ecosystem. Our tireless friends at Development Seed, GeoCompas, and GreenInfo Network somehow manage to keep us from falling off those broad shoulders. And of course, we wouldn’t have a project without our 1,464 contributors and counting.
On this 15th birthday of our domain name and sixth anniversary of the time slider, let’s hear it for our fabulously ambitious project and the people who make it a reality! How did you find out about OHM? What’s your favorite experience so far in contributing, using, or talking about the project?
