In reply to Bernard Shakey:
www.bikehike.co.uk
Go to the course creator, it's much the same as mapometer, but you can set it to use open street maps cycle which allows it to follow bridleways/footpaths rather than draw it manually. it's not perfect (occasiionally footpaths etc aren't joined, and you have to check what it's done and occasionally manually draw a small section.
Change the main map to OSM cycle (top right hand corner of the left map)
Then choose options in the bottom right.
Set routing algoritm to open street maps and travel mode to walking
Then zoom in to the area, and click away to create a course.
Use save route dialog box to change the settings as you need for your device. (it'll upload direct to garmin if you have the communicator plug-in)