

Plot a precise trail with elevation profile, using open data and software - andrewljohnson
http://blog.gaiagps.com/plot-a-precise-trail-with-the-gaia-gps-trail-finder/

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andrewljohnson
Here's the info about the tech from the blog:

The data comes from
[http://www.OpenStreetMap.org](http://www.OpenStreetMap.org).

The software uses the Valhalla
([https://mapzen.com/projects/valhalla](https://mapzen.com/projects/valhalla))
routing engine to generate routes, and the Pelias geocoder
([https://github.com/pelias](https://github.com/pelias)) to lookup names for
points. Valhalla and Pelias were both developed by Mapzen
([https://mapzen.com/](https://mapzen.com/)), an open-source mapping lab
dedicated to building open mapping tools that run on open data.

All routes between 60°S and 60°N include elevation profiles that are generated
from SRTM digital elevation models
([http://www2.jpl.nasa.gov/srtm/](http://www2.jpl.nasa.gov/srtm/)). The
digital elevation models were obtained from the Open Terrain project
([http://openterrain.tumblr.com/](http://openterrain.tumblr.com/)), who
provides easy access to terrain data that is freely available from US
government sites, but hard to access.

