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The US does have open mapping data: https://www.census.gov/geo/maps-data/data/tiger.html https://www.census.gov/geo/maps-data/data/tiger.html While useful for

The US does have open mapping data: https://www.census.gov/geo/maps-data/data/tiger.html https://www.census.gov/geo/maps-data/data/tiger.html While useful for taking the US Census, the TIGER data isn't really suitable for most navigation tasks. At best it can be used as a base layer to build a geospatial dataset. OpenStreetMap did this about a decade ago: https://wiki.openstreetmap.org/wiki/TIGER https://wiki.openstreetmap.org/wiki/TIGER That being said, the current administration is looking to cut TIGER funding, not increase it. For the foreseeable future getting mapping data suitable for navigation in the US is going to be the job of private for-profit companies.

ghaff 9y ago
I've read that a lot of the limitations/errors associated with mapping data once you get away from fully maintained paved roads stems from limitations in TIGER data. You get into very secondary roads and there's not much that's really authoritative to distinguish all the gradations between unpaved but well-graded and maintained and in appropriate weather you can drive it with high-clearance 4WD if you know what you're doing.
- maxerickson 9y ago
  For a navigation system those roads are mostly a "last mile" problem. They generally aren't as direct or connected as main highways, so graph based navigation naturally ignores them. Main highways are also reasonably well marked in the tiger data, so the lack of differentiation for the lower priority road type doesn't impact a system that prioritizes larger highways (a pretty reasonable heuristic). The lack of differentiation is a big problem if you want to pick which way to go when driving around though.
  - Doctor_Fegg 9y ago
    For a car navigation system, yes. For a bike navigation system it's a massive problem.
  - ghaff 9y ago
    I mostly agree with all that. Although in some areas like the rural US West, very secondary roads are pretty common. This becomes a bigger problem as more and more people depend on computers to tell them where to go without thinking much about it. Of course, this isn't really a new problem. People have died following roads on paper maps that weren't suitable for, say, winter travel.

ghaff 9y ago

I've read that a lot of the limitations/errors associated with mapping data once you get away from fully maintained paved roads stems from limitations in TIGER data. You get into very secondary roads and there's not much that's really authoritative to distinguish all the gradations between unpaved but well-graded and maintained and in appropriate weather you can drive it with high-clearance 4WD if you know what you're doing.

maxerickson 9y ago
For a navigation system those roads are mostly a "last mile" problem. They generally aren't as direct or connected as main highways, so graph based navigation naturally ignores them. Main highways are also reasonably well marked in the tiger data, so the lack of differentiation for the lower priority road type doesn't impact a system that prioritizes larger highways (a pretty reasonable heuristic). The lack of differentiation is a big problem if you want to pick which way to go when driving around though.
- Doctor_Fegg 9y ago
  For a car navigation system, yes. For a bike navigation system it's a massive problem.
- ghaff 9y ago
  I mostly agree with all that. Although in some areas like the rural US West, very secondary roads are pretty common. This becomes a bigger problem as more and more people depend on computers to tell them where to go without thinking much about it. Of course, this isn't really a new problem. People have died following roads on paper maps that weren't suitable for, say, winter travel.