Map distance different than actual distance on Garmin import.. (Read 468 times)

This sounds like a problem with the accuracy of the data points recorded on your forerunner. I have a 405 and (for me) there is normally a small difference between the "map" and "filled in" distance, but nothing of any great significance (20m to 100m over 30km). Is it possible that the route you took did not have a clear view of the sky (eg thick trees, buildings, tunnels )? If this is the case then the GPS position accuracy for at least some of the data points will be poor and will jump around compared to where you really went. The "map distance" is calculated from the length of the track between all the data points, so if they jump around then the map distance will be longer than the real distance. The "filled in distance" in the training log is taken from the distance recorded on your Garmin, and the watch seems to have some special calculations that give a more accurate distance measurement than the distance between the recorded data points. To "fix" the problem you could manually edit the map and correct the misplaced track points. To stop it happening in the first place you may need to find a route with a better view of the sky.