A customer asked me to redo their horse ring. The customer owns a stable and trains horses and riders so they need it done properly. I'm not familiar the requirements for a proper horse ring and was just about to start researching and figured I would post the question here, too. The customer said there should be a top layer of a couple of inches of clean sand. I am tentatively thinking to dig it down a foot and spread a base layer of process 8-10" and fine grade that. Then spread a 2-3" layer of clean concrete or mason sand. Just wondering if anyone here has any insight. Thanks.