I have had gravel paths for years. They were lined with weed cloth but over time weeds have grown through. So I started putting the straw from my chicken run (cleaned first) on top of the gravel. Then wonder lawn (dichondra) grew over it and it has proved to be a fabulous plant for the pathways. A thick, low growing mat that doesn't let weeds grow through it. If it grows into the beds it is easy to remove.