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I'm creating topo maps for my day hikes guides for national parks. I've already done one for Glacier National Park. When I was working on summits, I downloaded the data for Montana from GNIS and when I used the supplied elevations, I found it was different than the National Geographic maps, USGS topos and official Park handouts (all three had the same elevations). The problem appears to be that GNIS has DEM derived elevations.

I've scoured USGS's national map viewer, and the web at large trying to locate the data and am coming up short. I find pockets of data that seem to be grass roots efforts to basically do what I did and pull the elevations off of a USGS topo and put it in a table. I'd rather have the "official" elevations to save time and help with accuracy (instead of the propensity for me to fat finger it).

Anyone have a place to look?

  • Are you looking for this egsc.usgs.gov/isb//pubs/booklets/elvadist/elvadist.html scroll down at it has all 14,000+ peaks and east of rockies. – If you do not know- just GIS Oct 4 '14 at 2:48
  • Can you clarify "the Nat Geo" since I can read that as Geodetic or Geographic? Have you looked at the National Geodetic Survey benchmark dataset? Without knowing which points you're trying to identify and what their GNIS elevations are, it's hard to check if the NGS data has all of them or the values match what you're trying to. Have you tried contacting the NPS to determine the source dataset used in their maps? – Chris W Oct 4 '14 at 19:10
  • I've not seen that publication, @usertwoseventwothreenine, but when I went there, it's the problem that I usually run into where there is a small subset of data. For example, I'm currently looking for all of the summits in Zion which is 84. I'll be moving on to other national parks later and it would be nice to find the data that exists out there somewhere. – hike734 Oct 5 '14 at 15:56
  • @ChrisW I looked at the benchmark dataset for Zion National Park and, at the time, only found benchmarks along the road and nothing for summits. I checked with NPS and it's hodgepodge. I think that most of them inherited their data from previous GIS folks. But where did that original data come from... I've since emailed USGS and received an, "I'm not sure and the other gal in the office doesn't know either" kind of answer. I'm pressing to see if I can find someone on the teams that make the topos... or made them. If I get them, I'll try and figure out how to get that data into Openstreetmap. – hike734 Oct 5 '14 at 16:05
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    Have you also looked at the DLG datasets via Earth Explorer? As I understand it, those are the vector versions of the data that go into quad sheets. The Hypsography category turned up two file results for Zion at the large scale category and several for the 100k level though I didn't download and examine them. – Chris W Oct 5 '14 at 20:30

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