Garden Beds Gravel Base

Hi All,

I'm building wooden garden beds in the garden but need to raise ( approx. 3cm), level and compact the surface first. I have a lot of gravel already available and I'm thinking to utilise it but I'm worried it will be too loose for the base under garden beds. Also, I want to lay decorative white gravel on top (after separating it from the rest with a weed membrane).

Should I just drop the idea of using the gravel as a base or is there a way to make it work? E.g. filling it with sand.

Gravel should be fine with weight of the raised bed on it and would aid drainage. Dropping the base slightly below the finished gravel level will improve the appearance