Rainbow mountain accessibility

Hello, my friends and I are planning to go to the Rainbow Mountain in early October and would like to know if it is convenient to take some pictures (by a professional photographer) of a team of us (professional runners) running on the mountains...I basically would like to know how big the area is and if it is free to walk around or if there are pre-established paths for tourists only (like in many Chinese hotspots)...Is it possible to walk directly on the mountains or can you just stare at them from far distance?
Thanks for your kind reply
Nicola