This is a simple world historical map based on OpenHistoricalMap data that is suitable for embedding inside a third-party webpage. Using URL parameters, you can choose a location, time period, and cartographic style. To show a place’s evolution, you can also animate smoothly between two arbitrary dates. The map responds to gestures interactively, but the dates can only be adjusted via the URL.
Visit the map directly at embed.openhistoricalmap.org. Or export a code snippet for your webpage by opening the Share panel on the right side of OHM’s homepage and changing the format to “HTML”.
The URL has typical z/x/y parameters for map zoom and center.
So a parameter like #map=10/43.9367/12.5528 is zoom 10 showing San Marino in Italy, which is at 43.9367/12.5528 in lon,lat format of decimal degrees. See the map.
An embedded map is typically of a different size and aspect ratio from the original and thus must be scaled in order to cover a comparable area. This is accomplished by passing the original map's bounding box in the hash as &bbox=minlon,minlat,maxlon,maxlat. Once the embedded map gets its initial framing from the bbox the normal hash mechanism takes over. The San Marino example could be bounded by appending &bbox=12.321338653564453,43.86782687726672,12.58037567138672,44.008373185063874 to the URL. See this map.
Without a date parameter, the map shows everything in the OHM tiles for which there is a style specified.
OHM-specific parameters:
dateis a valid YYYY, YYYY-MM, or YYYY-MM-DD date, but we allow the year to be a variable number of digits or negative, unlike ISO 8601-1. So here is San Marino in the year 1500#map=10/43.9367/12.5528&date=1500. See this map.layerselects one of the OHM-compatible styles currently offered on openhistoricalmap.org:
| Map layer | layer |
Example |
|---|---|---|
| Historical | O |
New York in 1700 |
| Railway | R |
Sydney in 1924 |
| Woodblock | W |
San Marino in 1500 |
| Japanese Scroll | J |
Osaka in 1970 |
The map can optionally animate if you specify the following parameters:
start_dateis the initial value ofdateat the beginning of the animation. If you also specifydate, thestart_dateis ignored in favor ofdate.end_dateis the final value ofdateat the end of the animation.intervalis the difference in the dates depicted by any two consecutive frames of the animation, expressed as an ISO 8601-1 duration. For example,P10Y6M1Dadvances each frame by 10 years, 6 months, and 1 day, while-P10Y6M1Dturns back the clock by 10 years, 6 months, and 1 day on each frame. This parameter only supports years, months, and/or days. By default, the animation advances by one year at a time.framerateis the frequency of the animation measured in hertz, defaulting to1(1 hertz, or 1 frame per second).
By default, map labels appear in your preferred language according to your browser preferences. You can also override this preference by setting the language parameter to an ISO 639 language code. For example, add &language=cop&date=700 to see Roman Egypt labeled in Copt. If OHM doesn’t have the name of a place in this preferred language, the label appears in the contemporary local language as a last resort. To force the display of names in contemporary local languages, set the language parameter to mul (the ISO 639 code for multilingual content).
Simply use code like this to embed:
<iframe src="https://embed.openhistoricalmap.org/#map=10/43.9367/12.5528&date=1500&layer=O" height="500" width="100%" title="OpenHistoricalMap: San Marino in 1500"></iframe> Here's an example iframe.
Please submit bug reports and feature requests to OpenHistoricalMap’s central issue tracker, noting “OpenHistoricalMap embed” somewhere in the title or description.