Been doing a bit of armchair exploring and I've found these two websites.
Both websites allow you to register for free (register to download files).
They allow you to download routes so that you can view them with Google Earth. You can also download the files to use in various SatNav (GPS) and map formats. I downloaded a route in France (Route des Grandes Alpes) which has over twelve hundred points on it. TomTom .itn files allow a maximum of forty eight points. Using POIEdit (freeware) I reduced it to twenty five points so (basically by taking every fiftieth point). So I then had an .itn file that was usuable on the TomTom.
If you don't want all the hassle of converting stuff they do give you the chance to see the route before riding it. Make sure 'Terrain' is clicked in Google Earth so you can see how hilly / steep the route is.
(Armchair Exploring - you never get caught out in the rain and the coffee is always made how you like it).
Hope this is of some use to someone.