, would you perhaps know what type of ground would be best suited for a small jumping/multipurpose arena? How deep should it go?
Hello Jan ! I think the most important thing is that the ground is adapted to what you will do in your arena, it won't be the same if you practice jumping or western. Furthermore, it's really important for the horse's joints !
You also need to think about how you will maintain the good quality of the arena, every surfaces don't need the same maintenance (watering,...).
Your budget is an important a determining criterion ;)