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Good details on section just above the LLR - Lake Lanier Run are at https://georgiawildlife.wordpress.com/2014/05/21/upper-chattahoochee-river-fishing-and-public-access-points/ and its associated/linked map that I copied to upper-chattahoochee-access-points-map.png. Here's a bit more on this section; http://wildwoodoutfitters.com/more/upper-chattahoochee-river-water-trail/.
Great West Point to Riverview video including portage help for the few dams there.
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Chattahoochee Riverkeepers' Watershed Map.
Links to help plan a hike from Chattahoochee Gap down to Upper Chattahoochee Campground (i.e. the FIRST section of the river)
- https://gafw.org/headwaters-of-the-chattahoochee-hike-11-9-2019/
- https://www.alltrails.com/explore/trail/us/georgia/jacks-trail-to-red-clay-gap?mobileMap=false&ref=sidebar-static-map
- https://www.gaiagps.com/hike/poi/united-states/georgia/chattahoochee-oconee-national-forest-chatooga-district/upper-chattahoochee-river-campground/
- https://www.oldgrowthforest.net/ga-chattahoochee-headwaters-mark-trail-wilderness-chattahoochee-national-forest
- https://www.alltrails.com/trail/us/georgia/unicoi-gap-to-chattahoochee-gap
Campsite near beginning of the river; http://www.fs.usda.gov/recarea/conf/recreation/ohv/recarea/?recid=10501&actid=29
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