[Talk-us] TopOSM Colorado

[Lars Ahlzen]

Hi All!

It's been a while since the last TopOSM update, but I haven't been
resting. After Massachusetts, I decided to pick a state with somewhat 
more interesting topography: Colorado.

http://toposm.com/co/

There are still a few rough edges and things that are missing (like the
map legend), so consider it a "preview".

TopOSM-CO has a few important differences from TopOSM-MA:

* Color-by-elevation in base layer.

* Contour lines and hillshading generated from NED [1].

* Hydrography (lakes, rivers, wetlands etc) from NHD [2].

* The hillshading, contour lines and map features are on separate
layers. Use the layer switcher (top right "+") to toggle.

Since the data is nationwide, the same technique could (theoretically)
be used to generate a complete TopOSM map of the US, or even the world 
by using e.g. SRTM for elevation and OSM for hydrography.

I'll update the TopOSM wiki page [3] with the changes in this version as
soon as I can.

- Lars



[1] National Elevation Dataset. Available for the entire US.
http://ned.usgs.gov/

[2] National Hydrography Dataset. Available for the entire US. There is
some effort to import this into OSM, but we're not there yet.
http://nhd.usgs.gov/

[3] http://wiki.openstreetmap.org/wiki/TopOSM

-- 
Lars Ahlzen
lars at ahlzen.com