Friday, July 29, 2016

Pleiades Help: Getting Coordinates for a Place

Getting Coordinates for a Place
Creators: Tom Elliott Copyright © The Contributors. Sharing and remixing permitted under terms of the Creative Commons Attribution 3.0 License (cc-by).
Last modified Jul 27, 2016 06:00 PM

Coordinate information is stored in Pleiades "location" resources, which are grouped inside the "place" resources. We also calculate "representative points" (centroids) for each place on the basis of the associated locations. You can get whichever of these values is best for your purposes.
Portion of a place page, showing the location of the representative point and the clickable list of locations. 
Pleiades "place resources", e.g., are essentially containers for information about notional places (see further our Conceptual Overview). The maps on each place pull their coordinates from any "location resources" that have been assigned to that place. You'll see links to these under the "Locations" heading. If you click on a location there, you'll see information about the associated coordinates (points, lines, polygons), displayed in GeoJSON format.

For each Pleiades place resource, we calculate a "representative point" as well. This point -- which is the centroid of all associated locations -- is prominently displayed on the place page and rendered in the map on the place page with a distinctive orange circle. You can easily copy the representative point coordinates by selecting the "copy-to-clipboard" icon that appears immediately after the latitude and longitude coordinate pair under the "Representative Point" heading on the place page.

You can also download all of our data here: The places tables include "reprLong", "reprLat" and "reprLatLong" columns which hold the coordinates of a single representative point (centroid) for a place. If you'd just like the agreed upon, single representative latitude and longitude pair for a place, that's the best data source.


  1. It's good to know about this distinction between places and locations. Roughly what percentage of Pleiades locations are points? Are areas mostly bounding boxes, or are there some complex polygons? Thanks!

    1. I encourage you to connect directly with the community at Pleiades: