But even if you don't intend to ride a very long way all at once, but instead, say, in little bits and carrying a few things so you can spend the night along the way (read: touring).. the courses that the randonneurs take can be very useful for this!
Enter: permanents. Permanent courses developed by the S.I.Rs. Very handy indeed. Is there a randonneuring club in your area that has mapped some terrific routes?