On 08/09/2017 09:54, Colin Smale wrote:

Does anyone have any idea whether the elevations, be they in feet or metres, are all respecting the wiki definition of being the height above MSL according to EGM96 (not sure what that would mean in landlocked areas) and NOT WGS84 or (strictly speaking) relative to local MSL?

Not without checking the provenance of the data in OSM, no.  At least in the UK, peak ele values will have come from a variety of sources:

o "Well known values" that "the height of mountain X is Y"

o Some value copied from some other (hopefully out of copyright) map

o A value read from a GPS or phone.  With a bit of luck that person might have calibrated the barometer in that device recently, but there's no guarantee.  A non-barometric GPS-only derived elevation is likely to be even worse.

In the UK where I am, there are a significant number of peaks added by one mapper based on spot heights from old OS maps - many of these are not actually peaks at all, and many aren't in the correct place.

Best Regards,

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