OpenStreetMap extracts

The OpenStreetMap database gets bigger every day. The dataset is freely licensed and available in what we call a planet file. This means that if you want the OpenStreetMap dataset, you can have it. This also means that you are dealing with the entire dataset, for the whole planet, even if your interest is limited to a smaller area. If your interest is geographically limited, pushing around 6G¹ more data than you need to push around seems wasteful.

Fortunately we are not the first to notice the unwieldy size of the OSM database. There are tools to create smaller, fractional OpenStreetMap databases that are limited to one area. We, in the OpenStreetMap community, call these smaller databases, extracts.

Above is the extract of Luxembourg from GeoFabrik.

There are tools to create extracts and there are people who create extracts and share them with us. We saw how to create an extract from a planet file, using osmosis in a previous article. Some interesting extracts are provided in other places:

• OpenStreetMap extracts from GeoFabrik selected countries, continents and states.
• OpenStreetMap extracts from CloudMade selected countries and states.

And that makes it much easier to get started with OpenStreetMap if your interests are limited to one geographical area. Thanks, extract providers.

[1] The full planet file was 6.7G on 27 August 2009

Credits

Article © 2009 CCBY R.Weait.
Map images and data © 2009 CCBYSA OpenStreetMap and contributors.