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I am a developer, but the current context of the question is as a user: I don't want to spend time setting up OpenLayers server, writing code etc. for what I want to do.

Now, what I am trying to do:

I have downloaded a 112MB large KML file that should contain all the public lands in Nova Scotia, Canada from Socrata API: https://data.novascotia.ca/api/geospatial/3nka-59nz?method=export&format=KML (This can be exported to "Original, KMZ, Shapefile and GeoJSON" as well, if needed).

I tried loading it on Google Earth, and no luck, it hangs pretty much.

The reason I want to load it somehow, is to overlay it over normal satellite map with roads, so that I can pick exact geospatial coordinates, of places in public land, where I could for example camp with RV trailer, as once I have a coordinate, I can keep it in Google Maps, and navigate to it for our vacation plans.

After Refreshing Google Earth, it seems to have managed to open the imported KML project and even render the public land parcels, but it hangs, I cannot even more around/zoom in, it's just stuck in "Working"... I am looking I guess, for a native application that'd run locally, or any advice you can give please.

The Holy Grail answer I am looking for? Some Android mobile app where I can load the relevant KML data, and would show my location -- whether I am inside the shapes (e.g. public land), or not in real time overlaid over satellite/road view.

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  • For viewing on a phone or laptop?
    – Mapperz
    Mar 1, 2021 at 14:41
  • Phone preferable, but I have laptop as well if needed, Laptop is actually easier for planning and saving spots, phone easier for navigating to them while towing Mar 1, 2021 at 14:42
  • do you want the kml to be on google drive or available offline - i.e. on the device?
    – Mapperz
    Mar 1, 2021 at 15:51
  • Either way would work, preferable available offline but its not critical, especially if the specific area I am approaching, already has the borders of public space pre-loaded in session volatile RAM before connection is lost... Mar 1, 2021 at 20:15

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If the file has very high-res polygon data, then you can probably shrink it way down using "simplify geometry" type tools in your favorite GIS software. Looking at the data (map link), it appears to be LOTS of tiny polygons, so you might not be able to shrink it much that way. Then again, many of them are adjacent, so you could dissolve them (maybe buffer by a few meters to ensure overlap) to merge the polygons, and simplify the resulting geometries, and see if that's a more reasonable size.

If you just want this as a user for your own trip planning, then trying to use the vector data like this is probably best. But if you want to serve a dataset this big as part of a web map or app, then you'll likely need to find some solution that generates a pyramid of raster tiles from the vector data, and serve those instead.

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  • I am not sure dissolving is a good idea, it may create doubt, where I am parking outside of the public property.. This is for own trip planning, as I explained, I would like to reliably navigate satellite map and mark possible parking spots within the boundaries, then navigating to those using my phone. Mar 1, 2021 at 20:18
  • Just Dissolving would only combine polygons where they are already touching. "Buffering" would add a little area to each polygon, which could cause the issue you raise. That's why I suggested buffering just a few meters, which should take care of making sure the dissolve correctly combines adjacent polygons even if they are just slightly not touching, while not expanding the actual footprint significantly. Then again, I don't know how much it would help shrink the dataset for you, so up to you if it's worth trying. Sounds like a fun project and a fun trip!! Good luck. Mar 2, 2021 at 19:04
  • Could you please give me information on how to do this kind of dissolving that you are suggesting? I've never worked with KML files. Mar 4, 2021 at 4:55

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