There's a review on Amazon (https://www.amazon.co.uk/product-reviews/B010UPWVGU/ ) that states that the Etrex 35 doesn't support a single route with more than 50 waypoints in it, is that really true? That's quite a limitation, I'm aware than RWGPS doesn't use waypoints as such for it's routes, but I can see that being an issue for other types of map routing.
Normal for
Routes.
(Terminology is important here: In Garmin language a
Route is a list of places to go to in order, and a
Track is a line drawn on the map, typically by recording you walking/cycling/driving along.)
On the eTrex 30 the limit is 50
routepoints[1] for auto routing, or 250
routepoints in 'off-road' (crow flies lines between points) routing. As you don't need to represent every turn, just persuade the algorithm to pick the right roads, 50
routepoints should be good for about 100-200km of cycling with autorouting, and you can always use more than one
Route for a ride.
Most people here don't use
Routes at all though, they use
Tracks. Those have a limit of 10,000 points - good for representing every little turn for hundreds of kilometres, but following a
Track doesn't give you intelligent prompts at junctions.
[1] The points that make up a Route. Distinct from Trackpoints[2] or Waypoints[3].
[2] Points that make up a Track.
[3] Think of them as pins you stick in a map. You might navigate to one, but they're often just used to mark things.