Optimum length of Ring straps/climbing rope

Hi,

I am planning on including a ring setup and rope climb on an outdoor structure. I am thinking of hanging it up from a bar somewhere between 12 and 16 feet high. Are there things I won't be able to do at 12' that I could do at 16', and if there are, what are they? What is the minimum height to do different exercises that can't be done at 12'?  I am about 5'7".

Thank you,

Micha

There is not a fixed length for the rope. 5-6 mt is the general standard since the gymnastics facility is approximately 7-9 mt. for the rings there is no a fixed height, the longer the straps, the harder the skill over the rings.