Thanks Colin. We also know there are ruins of a village under the park so maybe that's it. Could be wrong. Ground Penetrating Radar was used to find the 3 buildings in tact. GPR works like an x-ray. You drill a hole, put the camera down and scan it bit by bit. I found the holes in the floor, so we know exactly where those buildings are from radar results sheets. As for the park, many folk won't know that there was a roman watch tower around the Old Hall. Fascinating history but very addictive...