I want to lay a gravel path in my yard and I'm wondering why I need to lay sand down first. Could I just use underlayment fabric, or do I really need the sand? Everything I have read says that I need to lay it down, but nothing says why. I would like to save as much money as possible, so if it's not really necessary, then I don't want to buy it!
If you're laying pavers, the sand is necessary to make things more level / keep weeds out but if you're just using gravel and nothing else, I don't see why you couldn't just lay ( optionally ) a border and then throw the gravel down. I'd personally use a border to keep the gravel from getting out.
Fabric ( in theory but never in my my experience ) would keep the weeds from coming up through the gravel but it seems to me that it would let the gravel move too much.
I am just going to use gravel, and I already bought the garden edge borders, so I will definitely be using those! I talked to someone else, and they said that the sand will help to keep the gravel from moving around. I would still like more feedback though. I kind of agree with you, that between the borders and fabric, it should be ok. At the same time, I'm doing this myself, and its a lot of work, so I really want it to last and be done right.