I have a gravel drive (some curvature) several hundred feet long. I'd like some way to create a clear deliniation between the gravel and the grass. I live in NEOhio - snow, frost, etc. I love the way large, rectangular stones (like old house foundation stones) look but I'm thinking they would be prohibitively expensive. What are some other options and their associated pros/cons? I realize if I do this I'll then have more weed-whacking to do, but am tired of how shoddy my current setup looks. I've also thought of trying to make my own rectangular blocks out of concrete a few at a time. Thanks for any thoughts and suggestions!