The USGS 3D Elevation Program (3DEP) is awesome. When mapping roads, creeks and trails that are covered by trees, it’s nearly impossible to use any satellite imagery in any meaningful way. Even if someone spends the time to use GPS to track a road or hiking trail, it is even harder to find someone to walk down the middle of a lot of creeks to track the path of the water flow. It’s also not uncommon for the GPS trace to be off by several feet or even have gaps in the data near tall dense trees, which reduces the accuracy of the path being traced on a map. 3DEP can help in such situations.

I believe that this data is only available for most of the US territories. So if you are mapping outside outside of the US, this may not be beneficial to use.

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