For young, or small breeds, i use a small wood frame pen, with it's sides and floor covered with fine wire (so that the cannot catch their feet), that stops the rabbits digging out, also things digging in, yet lets grass etc poke through and killding them etc, i have a a lid that is solid perspex with a woo fram so it provides a little shelter, inside this pen they haveand upturend dog/cat bed to hide under.
For larger or adult animalsthey run with the hens, with the basic builders pannels ans the surface fram, and chicken wire abuot 2feet up the pannels and dug down about a metre. DO NOT FORGET TO DIG WIRE UNDER THE DOOR
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hope this helps
I have nver had a rabbit escape through the mesh, or under it, but i had one a good few yers ago climb 6foot to escape, after that he was kept in a run with a lid