This is in many ways depend on the type of route you create. It can get very confusing.
There are at least three types of routes you can store on the Garmin Edge:
1. Route: the file extension is GPX. It allows for 100 points
2. Track: the file extension is GPX. It allows for 2,300 points. Garmin and some web sites state this as 16,363. Whenever I load a route with points more than 2,300, it gets truncated.
3. Course: the file extension in TCX. It allows > 18,000 points. Garmin manual state 16,363, but I tried a route at 18,000 points and there was no problem. The unit did not truncate it and displayed the correct total distance.
There are many details that compare the three types athttps://forums.garmin.com/showthread.php?t=17312