1. make a path (set line color, width and name by state and mileage). I just follow the roads using Sam’s maps, zooming in and out as necessary and clicking to add waypoints (you can hit delete to back up). My Tennessee maps are named like this 1TN 000.00 – 079.50. So that’s 1 for first state of my route and then the mileage that the route starts and ends on. Missippi starts with a 2MS 00000 – 062.30 That way they will be sequential by state and mileage in the GPS and coincide with Sam’s roll charts.
2. save in G earth as “save place as.”
3. open the .kml file that Google Earth made in GPSies.com and “convert” it to a gpx file. Make sure to choose “track” and then “gpx route.” There is a slider to set the number of waypoints (Nuvi 500 can only take 200 per route) and a Peucker algorithm to do it accurately. For my maps I set the slider at 200 and then use the low compression algorithm. Awesome free site with no sign in. I am def going to send a contribution.
I imported this back into G Earth just to see and it’s perfect. I guess it’s cutting out waypoints but I can’t tell where. (Really fun to press the little path symbol just below your files in Earth – it will fly you over the route you made.) Talk about an amazing free site!
4. open your new converted .gpx file in base camp (free download from Garmin but you need a gps to load maps into it). On my Mac I just double click the download from GPSies and it opens in B Camp.
5. plug your gps into the computer and it’ll show up in Base Camp. If your GPS has a data card it will appear as well.
5. drag gpx files into gps or gps memory card in base camp.
6. eject and at least on my Nuvi 500 I go to “my data” then “import route from file” and then select “custom route” and there it is loaded and ready to navigate!
7. Then manually add favorite on gps using coordinates or addresses for camping, food, gas, etc. (If anyone knows camp spots on the TAT I am interested!)
We tested a route we made in the car and it was great.
I tried using Google Maps instead of Earth because it has a line tool that will automatically snap to roads – nice. And it matches Sam’s map better than hunting from the air for roads in Earth. BUT… The routes created had way too many waypoints for my GPS to handle and the line drawing tool kept trying to re- route me to shorter distances on pavement (silly map it’s not the destination it’s the journey).
I hope this helps some folks. Also I don’t pretend to be an expert so please add corrections as needed.