5 ms·

If you're wanting to query the data importing into PostGIS is a fairly straightforward way to do it. And you don't have to download the whole planet in one go.

by olefoo 13y ago

bdon 13y ago
+1 to this. Metro Extracts: http://metro.teczno.com/ http://metro.teczno.com/ along with osm2pgsql: http://wiki.openstreetmap.org/wiki/Osm2pgsql http://wiki.openstreetmap.org/wiki/Osm2pgsql is the way to go.
- JamesChevalier 13y ago
  Be aware that those extracts are squares around the cities - they're not exact city border outlines. This means that you can't just use the data without concern for whether the things you're gathering are actually within the city or not. I haven't found a very simple way to get everything within exact city borders, yet. This is the process I've been going with so far: https://github.com/JamesChevalier/cities#cities https://github.com/JamesChevalier/cities#cities
  - olefoo 13y ago
    That is a very useful resource; thank you. Some cities make shapefiles available for urban growth boundaries and city limits. It's worth enquiring. But be aware that some cities city limits are not simple polygons; depending on local ordinances you can see islands, internal voids and peninsulas attached with zero width stems.
    - JamesChevalier 13y ago
      True! Like Houston, TX ... which looks a little like the flying spaghetti monster ... http://nominatim.openstreetmap.org/details.php?place_id=3675649666 http://nominatim.openstreetmap.org/details.php?place_id=3675... The poly files that you get from the process outlined in the readme file will include islands/voids. It's pretty cool.
  - rmc 13y ago
    Well remember OSM is an international project, so trying to find one definition of "city" and "border of a city" is hard. Some places (like USA) seem to use "city" as a hard solid thing, other places (eg UK / ireland) don't.
    - JamesChevalier 13y ago
      Yeah - OSM goes a long way in categorizing different levels of "area in which people live" based on population density. http://wiki.openstreetmap.org/wiki/Key:place http://wiki.openstreetmap.org/wiki/Key:place
      - rmc 13y ago
        Except that the place tag isn't always based on population size. In some places, (e.g. UK), a common cultural definition of a "city" is archaic, and depends if the place has a Cathedral and/or charter from the monarch. I give you the "city" of St. David's: http://www.openstreetmap.org/browse/node/3216768 http://www.openstreetmap.org/browse/node/3216768 It's in Wales, UK, and is tagged as "place=city". It's a small town of ~2,000 people. It has a charter from the monarch, and a cathedral. The "note" tag in OSM says: "the "city" is on paper, what's on the ground is a small town". Humanity is complicated. :)
        JamesChevalier 13y ago
        heh, true! I've been playing with place names & http://overpass-turbo.eu/ http://overpass-turbo.eu/ ... I seem to be getting the best results with "city|hamlet|metropolis|town|village", although some states like Alaska & Hawaii still don't return much with this scope. In Alaska, a lot of places are labeled as County. In Hawaii, a lot of places are labeled as Other.
        huxley 13y ago
        UK isn't the only place with weird "cities". Greenhorn, Oregon is designated as a city but has a 2010 census population of zero. Though now unicorporated, Tenny, Minnesota, was a city and had a peak population of 180 people in 1910 but now is down to 5 (2010 census).

If you're wanting to query the data importing into PostGIS is a fairly straightforward way to do it. And you don't have to download the whole planet in one go.

by olefoo 13y ago

If you're wanting to query the data importing into PostGIS is a fairly straightforward way to do it. And you don't have to download the whole planet in one go.

bdon 13y ago

+1 to this. Metro Extracts: http://metro.teczno.com/ http://metro.teczno.com/ along with osm2pgsql: http://wiki.openstreetmap.org/wiki/Osm2pgsql http://wiki.openstreetmap.org/wiki/Osm2pgsql is the way to go.

JamesChevalier 13y ago
Be aware that those extracts are squares around the cities - they're not exact city border outlines. This means that you can't just use the data without concern for whether the things you're gathering are actually within the city or not. I haven't found a very simple way to get everything within exact city borders, yet. This is the process I've been going with so far: https://github.com/JamesChevalier/cities#cities https://github.com/JamesChevalier/cities#cities
- olefoo 13y ago
  That is a very useful resource; thank you. Some cities make shapefiles available for urban growth boundaries and city limits. It's worth enquiring. But be aware that some cities city limits are not simple polygons; depending on local ordinances you can see islands, internal voids and peninsulas attached with zero width stems.
  - JamesChevalier 13y ago
    True! Like Houston, TX ... which looks a little like the flying spaghetti monster ... http://nominatim.openstreetmap.org/details.php?place_id=3675649666 http://nominatim.openstreetmap.org/details.php?place_id=3675... The poly files that you get from the process outlined in the readme file will include islands/voids. It's pretty cool.
- rmc 13y ago
  Well remember OSM is an international project, so trying to find one definition of "city" and "border of a city" is hard. Some places (like USA) seem to use "city" as a hard solid thing, other places (eg UK / ireland) don't.
  - JamesChevalier 13y ago
    Yeah - OSM goes a long way in categorizing different levels of "area in which people live" based on population density. http://wiki.openstreetmap.org/wiki/Key:place http://wiki.openstreetmap.org/wiki/Key:place
    - rmc 13y ago
      Except that the place tag isn't always based on population size. In some places, (e.g. UK), a common cultural definition of a "city" is archaic, and depends if the place has a Cathedral and/or charter from the monarch. I give you the "city" of St. David's: http://www.openstreetmap.org/browse/node/3216768 http://www.openstreetmap.org/browse/node/3216768 It's in Wales, UK, and is tagged as "place=city". It's a small town of ~2,000 people. It has a charter from the monarch, and a cathedral. The "note" tag in OSM says: "the "city" is on paper, what's on the ground is a small town". Humanity is complicated. :)
      - JamesChevalier 13y ago
        heh, true! I've been playing with place names & http://overpass-turbo.eu/ http://overpass-turbo.eu/ ... I seem to be getting the best results with "city|hamlet|metropolis|town|village", although some states like Alaska & Hawaii still don't return much with this scope. In Alaska, a lot of places are labeled as County. In Hawaii, a lot of places are labeled as Other.
      - huxley 13y ago
        UK isn't the only place with weird "cities". Greenhorn, Oregon is designated as a city but has a 2010 census population of zero. Though now unicorporated, Tenny, Minnesota, was a city and had a peak population of 180 people in 1910 but now is down to 5 (2010 census).