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Help:Nominatim

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Nominatim is a tool used to search OpenGeofiction data and address points by geocoding. Nominatim is used by the search bar on the main OpenGeofiction map. The Nominatim database and API are hosted by infinatious.

Hosting information

Documentation for Nominatim can be found at the Nominatim project website. 100% uptime is not guaranteed.

Usage policy

Please follow the same usage policy for OpenGeofiction and the OSM Nominatim policy.

FAQ

What is Nominatim useful for?

Nominatim can be used to search the OpenGeofiction map for places. It allow allows for reverse search, which allows you to do a lookup on what is at particular coordinates.

How often is the data updated?

Currently, the Nominatim database is manually refreshed weekly on Thursdays around 1500 UTC. You can check the exact time of the most recent data on the debug interface above, in the top right corner. The refresh process involves about 2 hours of downtime.

Why is a real-world or the wrong country displayed?

A real world country or the wrong OpenGeofiction country can be displayed for approximately 5 hours after the refresh process, as that is how long it takes to run the country index process. Please wait several hours and try again.

Why am I receiving a Cloudflare error?

If you are receiving a Cloudflare error, please check the status page above. Infinatious is generally aware of outages and will work to restore service as quickly as possible. If the status page is showing the service is up, please contact Infinatious.

Why are my places showing in the wrong administrative entity?

This can be due to the fact that Nominatim computes a median point for every object it indexes. For example, if you have a street that goes through multiple cities without being divided into multiple segments, Nominatim will usually associated it with the "middle" city. The solution is to divide the street at every administrative boundary. For suburbs (and other small things like villages/hamlets), Nominatim will sometimes ignore the next higher admin-level (usually city/municipality) and associate it directly with the county. In that case, it is recommended to tag is_in=* to the corresponding relation, usually the is_in:city=* to the relation of the suburb/village/hamlet is enough.

Tips & tricks

  • For nodes with place tags, include these in your relations with the label role.
  • Divide streets and other places at each administrative boundary.
  • Use the is_in= tag on administrative relations. ( more information).