There’s a function on my Garmin Edge 1000 that I haven’t used yet. You specify a distance for your ‘adventure’ based relative to your current location, and the device shows you some suggested cycling routes and provides navigation and turn-by-turn instructions. Out on the route, you can invoke a ‘get me home’ function at any time.

It’s supposed to be a great feature for exploring nearby areas.

Perhaps others have used this feature already and can provide more information?